def open(self):
"""Open the serial port
Configure serial port to be opened."""
if self.simulate:
self.ser = DAQSimulator(self.port, BAUDS, timeout=1)
else:
self.ser = serial.Serial(self.port, BAUDS, timeout=1)
self.ser.setRTS(0)
time.sleep(2)
def open(self):
"""Open the serial port
Configure serial port to be opened."""
if self.simulate:
self.ser = DAQSimulator(self.port, BAUDS, timeout=1)
else:
self.ser = serial.Serial(self.port, BAUDS, timeout=1)
self.ser.setRTS(0)
time.sleep(2)
class DAQ(threading.Thread):
def __init__(self, port, debug=False):
"""Class constructor"""
threading.Thread.__init__(self)
self.port = port
self.debug = debug
self.simulate = (port == 'sim')
self.__running = False
self.__measuring = False
self.__stopping = False
self.gain = 0
self.pinput = 1
self.open()
info = self.get_info()
self.__fw_ver = info[1]
self.__hw_ver = 'm' if info[0] == 1 else 's'
self.gains, self.offsets = self.get_cal()
self.dac_gain, self.dac_offset = self.get_dac_cal()
self.experiments = []
self.preload_data = None
def open(self):
"""Open the serial port
Configure serial port to be opened."""
if self.simulate:
self.ser = DAQSimulator(self.port, BAUDS, timeout=1)
else:
self.ser = serial.Serial(self.port, BAUDS, timeout=1)
self.ser.setRTS(0)
time.sleep(2)
def close(self):
"""Close the serial port"""
self.ser.close()
def send_command(self, command, ret_fmt):
"""Build a command packet, send it to the openDAQ and process the
response
Args:
cmd: Command string
ret_fmt: Payload format of the response using python
'struct' format characters
Returns:
Command ID and arguments of the response
Raises:
LengthError: The legth of the response is not the expected
"""
fmt = '!BB' + ret_fmt
ret_len = 2 + struct.calcsize(fmt)
self.ser.write(command)
ret = self.ser.read(ret_len)
if self.debug:
print 'Command: ',
for c in command:
print '%02X' % ord(c),
print
print 'Response: ',
for c in ret:
print '%02X' % ord(c),
print
if ret == NAK:
raise IOError("NAK response received")
data = struct.unpack(fmt, check_crc(ret))
if len(ret) != ret_len:
raise LengthError("Bad packet length %d (it should be %d)" %
(len(ret), ret_len))
if data[1] != ret_len - 4:
raise LengthError("Bad body length %d (it should be %d)" %
(ret_len - 4, data[1]))
# Strip 'command' and 'length' values from returned data
return data[2:]
def get_info(self):
"""Read device configuration
Returns:
[hardware version, firmware version, device ID number]
"""
return self.send_command(mkcmd(39, ''), 'BBI')
def device_info(self):
"""Return device configuration
Returns:
[hardware version, firmware version, device ID number]
"""
hv, fv, serial = self.get_info()
print "Hardware Version: ", "[M]" if hv == 1 else "[S]"
print "Firmware Version:", fv
print "Serial number: OD" + ("M08" if hv == 1 else
"S08") + str(serial).zfill(3) + "5"
def hw_ver(self):
return self.__hw_ver
def fw_ver(self):
return self.__fw_ver
def read_adc(self):
"""Read data from ADC and return the raw value
Returns:
Raw ADC value
"""
return self.send_command(mkcmd(1, ''), 'h')[0]
def read_analog(self):
"""Read data from ADC in volts
Returns:
Voltage value
"""
value = self.send_command(mkcmd(1, ''), 'h')[0]
# Raw value to voltage->
index = self.gain + 1 if self.__hw_ver == 'm' else self.pinput
value *= self.gains[index]
value = -value / 1e5 if self.__hw_ver == 'm' else value / 1e4
value = (value + self.offsets[index]) / 1e3
return value
def read_all(self, nsamples=20, gain=0):
"""Read data from all analog inputs
Args:
nsamples: Number of samples per data point [0-255] (default=20)
gain: Analog gain
openDAQ[M]= [0:4] (x1/3, x1, x2, x10, x100)
openDAQ[S]= [0:7] (x1,x2,x4,x5,x8,x10,x16,x20)
(default=1)
Returns:
Values[0:7]: List of the analog reading on each input
"""
if self.fw_ver() < 120:
raise Warning("Function not implemented in this FW. Try updating")
self.gain = gain
values = self.send_command(mkcmd(4, 'BB', nsamples, gain), '8h')
if self.__hw_ver == 'm':
a = -self.gains[self.gain + 1] / 1e5
b = self.offsets[self.gain + 1]
val = [(v * a + b) / 1e3 for v in values]
else:
val = [(v * self.gains[i + 1] / 1e4 + self.offsets[i + 1]) / 1e3
for i, v in enumerate(values)]
return val
def conf_adc(self, pinput=8, ninput=0, gain=0, nsamples=20):
"""
Configure the analog-to-digital converter.
Get the parameters for configure the analog-to-digital
converter.
Args:
pinput: Positive input [1:8]
ninput: Negative input
openDAQ[M]= [0, 5, 6, 7, 8, 25]
openDAQ[S]= [0,1:8] (must be 0 or pinput-1)
gain: Analog gain
openDAQ[M]= [0:4] (x1/3, x1, x2, x10, x100)
openDAQ[S]= [0:7] (x1,x2,x4,x5,x8,x10,x16,x20)
nsamples: Number of samples per data point [0-255)
Raises:
ValueError: Values out of range
"""
if not 1 <= pinput <= 8:
raise ValueError("positive input out of range")
if self.__hw_ver == 'm' and ninput not in [0, 5, 6, 7, 8, 25]:
raise ValueError("negative input out of range")
if self.__hw_ver == 's' and ninput != 0 and (
pinput % 2 == 0 and ninput != pinput - 1
or pinput % 2 != 0 and ninput != pinput + 1):
raise ValueError("negative input out of range")
if self.__hw_ver == 'm' and not 0 <= gain <= 4:
raise ValueError("gain out of range")
if self.__hw_ver == 's' and not 0 <= gain <= 7:
raise ValueError("gain out of range")
if not 0 <= nsamples < 255:
raise ValueError("samples number out of range")
self.gain = gain
if self.__hw_ver == 's' and ninput != 0:
self.pinput = (pinput - 1) / 2 + 9
else:
self.pinput = pinput
return self.send_command(
mkcmd(2, 'BBBB', pinput, ninput, gain, nsamples), 'hBBBB')
def enable_crc(self, on):
"""Enable/Disable the cyclic redundancy check
Args:
on: Enable CRC
Raises:
ValueError: on value out of range
"""
if on not in [0, 1]:
raise ValueError("on value out of range")
return self.send_command(mkcmd(55, 'B', on), 'B')[0]
def set_led(self, color):
"""Choose LED status.
LED switch on (green, red or orange) or switch off.
Args:
color: LED color (0:off, 1:green, 2:red, 3:orange)
Raises:
ValueError: Invalid color number
"""
if not 0 <= color <= 3:
raise ValueError('Invalid color number')
return self.send_command(mkcmd(18, 'B', color), 'B')[0]
def __volts_to_raw(self, volts):
"""Convert a value in volts to a raw value.
Device calibration values are used for the calculation.
openDAQ[M] range: -4.096 V to +4.096 V
openDAQ[S] range: 0 V to +4.096 V
Args:
volts: value to convert to raw
Returns:
Raw value
Raises:
ValueError: DAC voltage out of range
"""
value = int(round(volts * 1000))
if self.__hw_ver == 'm' and not -4096 <= value < 4096:
raise ValueError('DAC voltage out of range')
elif self.__hw_ver == 's' and not 0 <= value < 4096:
raise ValueError('DAC voltage out of range')
data = 2 * (value * self.dac_gain / 1000.0 + self.dac_offset + 4096)
if self.__hw_ver == 's':
data = max(0, min(data, 65535)) # clamp value
return data
def set_analog(self, volts):
"""Set DAC output voltage (millivolts value).
Set the output voltage value between the voltage hardware limits.
Device calibration values are used for the calculation.
openDAQ[M] range: -4.096 V to +4.096 V
openDAQ[S] range: 0 V to +4.096 V
Args:
volts: New DAC output value in millivolts
Raises:
ValueError: DAC voltage out of range
"""
if self.__hw_ver == 'm' and not -4096 <= volts < 4096:
raise ValueError('DAC voltage out of range')
elif self.__hw_ver == 's' and not 0 <= volts < 4096:
raise ValueError('DAC voltage out of range')
data = self.__volts_to_raw(volts)
self.set_dac(data)
def set_dac(self, raw):
"""Set DAC output (binary value)
Set the raw value into DAC without data conversion.
Args:
raw: RAW binary ADC data value.
Raises:
ValueError: DAC voltage out of range
"""
value = int(round(raw))
if (self.__hw_ver == 'm'
and not 0 <= value < 16384) or (self.__hw_ver == 's'
and not 0 <= value < 65536):
raise ValueError('DAC value out of range')
return self.send_command(mkcmd(24, 'H', value), 'h')[0]
def set_port_dir(self, output):
"""Configure all PIOs directions.
Set the direction of all D1-D6 terminals.
Args:
output: Port directions byte (bits: 0:input, 1:output)
Raises:
ValueError: output value out of range
"""
if not 0 <= output < 64:
raise ValueError("output value out of range")
return self.send_command(mkcmd(9, 'B', output), 'B')[0]
def set_port(self, value):
"""Write all PIO values
Set the value of all D1-D6 terminals.
Args:
value: Port output byte (bits: 0:low, 1:high)
Returns:
Real value of the port. Output pin as fixed in value\
input pin refresh with current state.
Raises:
ValueError: port output byte out of range
"""
if not 0 <= value < 64:
raise ValueError("port output byte out of range")
return self.send_command(mkcmd(7, 'B', value), 'B')[0]
def set_pio_dir(self, number, output):
"""Configure PIO direction
Set the direction of a specific PIO terminal (D1-D6).
Args:
number: PIO number [1:6]
output: PIO direction (0 input, 1 output)
Raises:
ValueError: Invalid PIO number
"""
if not 1 <= number <= 6:
raise ValueError('Invalid PIO number')
if output not in [0, 1]:
raise ValueError("PIO direction out of range")
return self.send_command(mkcmd(5, 'BB', number, int(bool(output))),
'BB')
def set_pio(self, number, value):
"""Write PIO output value
Set the value of the PIO terminal (0: low, 1: high).
Args:
number: PIO number (1-6)
value: digital value (0: low, 1: high)
Raises:
ValueError: Invalid PIO number
"""
if not 1 <= number <= 6:
raise ValueError('Invalid PIO number')
if value not in [0, 1]:
raise ValueError("digital value out of range")
return self.send_command(mkcmd(3, 'BB', number, int(bool(value))),
'BB')
def init_counter(self, edge):
"""Initialize the edge Counter
Configure which edge increments the count:
Low-to-High (1) or High-to-Low (0).
Args:
edge: high-to-low (0) or low-to-high (1)
Raises:
ValueError: edge value out of range
"""
if edge not in [0, 1]:
raise ValueError("edge value out of range")
return self.send_command(mkcmd(41, 'B', edge), 'B')[0]
def get_counter(self, reset):
"""Get the counter value
Args:
reset: reset the counter after perform reading (>0: reset)
Raises:
ValueError: reset value out of range
"""
if not 0 <= reset <= 255:
raise ValueError("reset value out of range")
return self.send_command(mkcmd(42, 'B', reset), 'H')[0]
def init_capture(self, period):
"""Start Capture mode around a given period
Args:
period: estimated period of the wave (in microseconds)
Raises:
ValueError: period out of range
"""
if not 0 <= period <= 65535:
raise ValueError("period out of range")
return self.send_command(mkcmd(14, 'H', period), 'H')[0]
def stop_capture(self):
"""Stop Capture mode
"""
self.send_command(mkcmd(15, ''), '')
def get_capture(self, mode):
"""Get Capture reading for the period length
Low cycle, High cycle or Full period.
Args:
mode: Period length
0: Low cycle
1: High cycle
2: Full period
Returns:
mode
Period: The period length in microseconds
Raises:
ValueError: mode value out of range
"""
if mode not in [0, 1, 2]:
raise ValueError("mode value out of range")
return self.send_command(mkcmd(16, 'B', mode), 'BH')
def init_encoder(self, resolution):
"""Start Encoder function
Args:
resolution: Maximum number of ticks per round [0:65535]
Raises:
ValueError: resolution value out of range
"""
if not 0 <= resolution <= 65535:
raise ValueError("resolution value out of range")
return self.send_command(mkcmd(50, 'B', resolution), 'B')[0]
def get_encoder(self):
"""Get current encoder relative position
Returns:
Position: The actual encoder value.
"""
return self.send_command(mkcmd(52, ''), 'H')[0]
def stop_encoder(self):
"""Stop encoder"""
self.send_command(mkcmd(51, ''), '')
def init_pwm(self, duty, period):
"""Start PWM output with a given period and duty cycle
Args:
duty: High time of the signal [0:1023](0 always low,\
1023 always high)
period: Period of the signal (microseconds) [0:65535]
Raises:
ValueError: Values out of range
"""
if not 0 <= duty < 1024:
raise ValueError("duty value out of range")
if not 0 <= period <= 65535:
raise ValueError("period value out of range")
return self.send_command(mkcmd(10, 'HH', duty, period), 'HH')
def stop_pwm(self):
"""Stop PWM"""
self.send_command(mkcmd(11, ''), '')
def __get_calibration(self, gain_id):
"""
Read device calibration for a given analog configuration
Gets calibration gain and offset for the corresponding analog
configuration
Args:
gain_id: analog configuration
(0:5 for openDAQ [M])
(0:16 for openDAQ [S])
Returns:
gain_id
Gain (x100000[M] or x10000[S])
Offset
Raises:
ValueError: gain_id out of range
"""
if (self.__hw_ver == 'm'
and not 0 <= gain_id <= 5) or (self.__hw_ver == 's'
and not 0 <= gain_id <= 16):
raise ValueError("gain_id out of range")
return self.send_command(mkcmd(36, 'B', gain_id), 'BHh')
def get_cal(self):
"""
Read device calibration
Gets calibration values for all the available device configurations
Returns:
Gains
Offsets
"""
gains = []
offsets = []
_range = 6 if self.__hw_ver == "m" else 17
for i in range(_range):
gain_id, gain, offset = self.__get_calibration(i)
gains.append(gain)
offsets.append(offset)
return gains, offsets
def get_dac_cal(self):
"""
Read DAC calibration
Returns:
DAC gain
DAC offset
"""
gain_id, gain, offset = self.__get_calibration(0)
return gain, offset
def __set_calibration(self, gain_id, gain, offset):
"""
Set device calibration
Args:
gain_id: ID of the analog configuration setup
gain: Gain multiplied by 100000 ([M]) or 10000 ([S])
offset: Offset raw value (-32768 to 32768)
Raises:
ValueError: Values out of range
"""
if (self.__hw_ver == 'm'
and not 0 <= gain_id <= 5) or (self.__hw_ver == 's'
and not 0 <= gain_id <= 16):
raise ValueError("gain_id out of range")
if not 0 <= gain < 65536:
raise ValueError("gain out of range")
if not -32768 <= offset < 32768:
raise ValueError("offset out of range")
return self.send_command(mkcmd(37, 'BHh', gain_id, gain, offset),
'BHh')
def set_cal(self, gains, offsets, flag):
"""
Set device calibration
Args:
gains: Gain multiplied by 100000 ([M]) or 10000 ([S])
offsets: Offset raw value (-32768 to 32768)
flag: 'M', 'SE' or 'DE'
Raises:
ValueError: Values out of range
"""
for gain in gains:
if not 0 <= gain < 65536:
raise ValueError("gain out of range")
for offset in offsets:
if not -32768 <= offset < 32768:
raise ValueError("offset out of range")
if flag == 'M':
for i in range(1, 6):
self.__set_calibration(i, gains[i - 1], offsets[i - 1])
elif flag == 'SE':
for i in range(1, 9):
self.__set_calibration(i, gains[i - 1], offsets[i - 1])
elif flag == 'DE':
for i in range(9, 17):
self.__set_calibration(i, gains[i - 9], offsets[i - 9])
else:
raise ValueError("Invalid flag")
def set_dac_cal(self, gain, offset):
"""
Set DAC calibration
Args:
gain: Gain multiplied by 100000 ([M]) or 10000 ([S])
ofset: Offset raw value (-32768 to 32678)
Raises:
ValueError: Values out of range
"""
if not 0 <= gain < 65536:
raise ValueError("gain out of range")
if not -32768 <= offset < 32768:
raise ValueError("offset out of range")
self.__set_calibration(0, gain, offset)
def __raw_to_volts(self, raw, experiment):
"""Convert a raw value to a value in volts.
Args:
raw: Value to convert to volts
experiment: DataChannel number of this experiment
"""
if not 0 <= experiment <= 3:
raise ValueError('Invalid experiment number')
gain_id, pinput, ninput, number = (
self.experiments[experiment].get_parameters())
if self.__hw_ver == 'm':
gain = self.gains[gain_id + 1]
offset = self.offsets[gain_id + 1]
volts = float(raw)
volts *= gain
volts = -volts / 1e5
volts = (volts + offset) / 1e3
if self.__hw_ver == 's':
n = pinput
if ninput != 0:
n += 8
gain = self.gains[n]
offset = self.offsets[n]
volts = ((float(raw * gain)) / 1e4 + offset)
volts /= MULTIPLIER_LIST[gain_id]
volts /= 1000.0
return volts
def set_id(self, id):
"""
Identify openDAQ device
Args:
id: id number of the device [000:999]
Raises:
ValueError: id out of range
"""
if not 0 <= id < 1000:
raise ValueError('id out of range')
return self.send_command(mkcmd(39, 'I', id), 'bbI')
def spi_config(self, cpol, cpha):
"""Bit-Bang SPI configure (clock properties)
Args:
cpol: Clock polarity (clock pin state when inactive)
cpha: Clock phase (leading 0, or trailing 1 edges read)
Raises:
ValueError: Invalid spisw_config values
"""
if not 0 <= cpol <= 1 or not 0 <= cpha <= 1:
raise ValueError('Invalid spisw_config values')
return self.send_command(mkcmd(26, 'BB', cpol, cpha), 'BB')
def spi_setup(self, nbytes, sck=1, mosi=2, miso=3):
"""Bit-Bang SPI setup (PIO numbers to use)
Args:
nbytes: Number of bytes
sck: Clock pin
mosi: MOSI pin (master out / slave in)
miso: MISO pin (master in / slave out)
Raises:
ValueError: Invalid values
"""
if not 0 <= nbytes <= 3:
raise ValueError('Invalid number of bytes')
if not 1 <= sck <= 6 or not 1 <= mosi <= 6 or not 1 <= miso <= 6:
raise ValueError('Invalid spisw_setup values')
return self.send_command(mkcmd(28, 'BBB', sck, mosi, miso), 'BBB')
def spi_write(self, value, word=False):
"""Bit-bang SPI transfer (send+receive) a byte or a word
Args:
value: Data to send (byte/word to transmit)
word: send a 2-byte word, instead of a byte
Raises:
ValueError: Value out of range
"""
if not 0 <= value <= 65535:
raise ValueError("value out of range")
if word:
ret = self.send_command(mkcmd(29, 'H', value), 'H')[0]
else:
ret = self.send_command(mkcmd(29, 'B', value), 'B')[0]
return ret
def __conf_channel(self,
number,
mode,
pinput=1,
ninput=0,
gain=1,
nsamples=1):
"""
Configure a channel for a generic stream experiment.
(Stream/External/Burst).
Args:
- number: Select a DataChannel number for this experiment
- mode: Define data source or destination [0:5]:
0) ANALOG_INPUT
1) ANALOG_OUTPUT
2) DIGITAL_INPUT
3) DIGITAL_OUTPUT
4) COUNTER_INPUT
5) CAPTURE_INPUT
- pinput: Select Positive/SE analog input [1:8]
- ninput: Select Negative analog input:
openDAQ[M]= [0, 5, 6, 7, 8, 25]
openDAQ[S]= [0,1:8] (must be 0 or pinput-1)
- gain: Select PGA multiplier.
In case of openDAQ [M]:
0. x1/2
1. x1
2. x2
3. x10
4. x100
In case of openDAQ [S]:
0. x1
1. x2
2. x4
3. x5
4. x8
5. x10
6. x16
7. x20
- nsamples: Number of samples to calculate the mean for each point\
[0:255].
Raises:
ValueError: Values out of range
"""
if not 1 <= number <= 4:
raise ValueError('Invalid number')
if type(mode) == int and not 0 <= mode <= 5:
raise ValueError('Invalid mode')
if type(mode) == str:
if mode in INPUT_MODES:
mode = INPUT_MODES.index(mode)
else:
raise ValueError('Invalid mode')
if not 0 <= pinput <= 8:
raise ValueError('pinput out of range')
if self.__hw_ver == 'm' and ninput not in [0, 5, 6, 7, 8, 25]:
raise ValueError("negative input out of range")
if self.__hw_ver == 's' and ninput != 0 and (
pinput % 2 == 0 and ninput != pinput - 1
or pinput % 2 != 0 and ninput != pinput + 1):
raise ValueError("negative input out of range")
if self.__hw_ver == 'm' and not 0 <= gain <= 4:
raise ValueError("gain out of range")
if self.__hw_ver == 's' and not 0 <= gain <= 7:
raise ValueError("gain out of range")
if not 0 <= nsamples < 255:
raise ValueError("samples number out of range")
return self.send_command(
mkcmd(22, 'BBBBBB', number, mode, pinput, ninput, gain, nsamples),
'BBBBBB')
def __setup_channel(self, number, npoints, continuous=False):
"""
Configure the experiment's number of points
Args:
number: Select a DataChannel number for this experiment
npoints: Total number of points for the experiment
[0:65536] (0 indicates continuous acquisition)
continuous: Indicates if experiment is continuous
False run once
True continuous
Raises:
ValueError: Values out of range
"""
if not 1 <= number <= 4:
raise ValueError('Invalid number')
if not 0 <= npoints < 65536:
raise ValueError('npoints out of range')
return self.send_command(
mkcmd(32, 'BHb', number, npoints, int(not continuous)), 'BHB')
def remove_experiment(self, experiment):
"""
Delete a single experiment
Args:
experiment: reference of the experiment to remove
Raises:
ValueError: Invalid reference
"""
nb = experiment.get_parameters()[3]
if not 1 <= nb <= 4:
raise ValueError('Invalid reference')
self.__destroy_channel(nb)
for i in range(len(self.experiments))[::-1]:
if self.experiments[i].number == nb:
del (self.experiments[i])
def clear_experiments(self):
"""
Delete the whole experiment list
Args:
None
"""
for i in range(len(self.experiments))[::-1]:
self.__destroy_channel(i + 1)
del (self.experiments[i])
def dchanindex(self):
"""
Check which internal DataChannels are used or available
Args:
None
Returns:
available: list of free DataChannels
used: list of asigned DataChannels
"""
used = [e.number for e in self.experiments]
available = [i for i in range(1, 5) if i not in used]
return available, used
def __destroy_channel(self, number):
"""
Command firmware to clear a Datachannel structure
Args:
number: Number of DataChannel structure to clear
[0:4] (0: reset all DataChannels)
Raises:
ValueError: Invalid number
"""
if not 1 <= number <= 4:
raise ValueError('Invalid number')
return self.send_command(mkcmd(57, 'B', number), 'B')[0]
def create_stream(self, mode, *args, **kwargs):
"""
Create Stream experiment
See class constructor for more info
"""
available, used = self.dchanindex()
index = len(self.experiments)
if index > 0 and self.experiments[0].__class__ is DAQBurst:
raise LengthError('Device is configured for a Burst experiment')
if len(available) == 0:
raise LengthError('Only 4 experiments available at a time')
if mode == ANALOG_OUTPUT:
chan = 4 # DAC_OUTPUT is fixed at DataChannel 4
for i in range(index):
if self.experiments[i].number == chan:
if type(self.experiments[i]) is DAQStream:
self.experiments[i].number = available[0]
else:
raise ValueError('DataChannel 4 is being used')
else:
chan = available[0]
self.experiments.append(DAQStream(mode, chan, *args, **kwargs))
return self.experiments[index]
def __create_stream(self, number, period):
"""
Send a command to the firmware to create Stream experiment
Args:
number: Assign a DataChannel number for this experiment [1:4]
period: Period of the stream experiment
(milliseconds) [1:65536]
Raises:
ValueError: Invalid values
"""
if not 1 <= number <= 4:
raise ValueError('Invalid number')
if not 1 <= period <= 65535:
raise ValueError('Invalid period')
return self.send_command(mkcmd(19, 'BH', number, period), 'BH')
def create_external(self, mode, clock_input, *args, **kwargs):
"""
Create External experiment
See class constructor for more info
"""
available, used = self.dchanindex()
index = len(self.experiments)
if index > 0 and self.experiments[0].__class__ is DAQBurst:
raise LengthError('Device is configured for a Burst experiment')
if len(available) == 0:
raise LengthError('Only 4 experiments available at a time')
for i in range(index):
if self.experiments[i].number == clock_input:
if type(self.experiments[i]) is DAQStream:
self.experiments[i].number = available[0]
else:
raise ValueError(
'Clock_input is being used by another experiment')
self.experiments.append(DAQExternal(mode, clock_input, *args,
**kwargs))
return self.experiments[index]
def __create_external(self, number, edge):
"""
Send a command to the firmware to create External experiment
Args:
number: Assign a DataChannel number for this experiment [1:4]
edge: New data on rising (1) or falling (0) edges [0:1]
Raises:
ValueError: Invalid values
"""
if not 1 <= number <= 4:
raise ValueError('Invalid number')
if edge not in [0, 1]:
raise ValueError('Invalid edge')
return self.send_command(mkcmd(20, 'BB', number, edge), 'BB')
def create_burst(self, *args, **kwargs):
"""
Create Burst experiment
"""
if len(self.experiments) > 0:
raise ValueError(
'Only 1 experiment available at a time if using burst')
self.experiments.append(DAQBurst(*args, **kwargs))
return self.experiments[0]
def __create_burst(self, period):
"""
Send a command to the firmware to create Burst experiment
Args:
period: Period of the burst experiment
(microseconds) [100:65535]
Raises:
ValueError: Invalid period
"""
if not 100 <= period <= 65535:
raise ValueError('Invalid period')
return self.send_command(mkcmd(21, 'H', period), 'H')
def __load_signal(self, pr_of, pr_data):
"""
Load an array of values in volts to preload DAC output
Raises:
LengthError: Invalid dada length
"""
if not 1 <= len(pr_data) <= 400:
raise LengthError('Invalid data length')
values = []
self.set_analog(pr_data[0])
for volts in pr_data:
raw = self.__volts_to_raw(volts)
'''
if self.__hw_ver == "s":
raw *= 2
'''
values.append(raw)
return self.send_command(
mkcmd(23, 'h%dH' % len(values), pr_of, *values), 'Bh')
def flush(self):
"""
Flush internal buffers
"""
self.ser.flushInput()
def get_stream(self, data, channel):
"""
Serial parser.
Low-level function for stream data collecting.
Args:
data: Buffer for data points
channel: Buffer for assigned experiment number
Returns:
0 if there is not any incoming data.
1 if data stream was processed.
2 if no data stream received.
"""
self.header = []
self.data = []
ret = self.ser.read(1)
if not ret:
return 0
head = struct.unpack('!b', ret)
if head[0] != 0x7E:
data.append(head[0])
return 2
# Get header
while len(self.header) < 8:
ret = self.ser.read(1)
char = struct.unpack('!B', ret)
if char[0] == 0x7D:
ret = self.ser.read(1)
char = struct.unpack('!B', ret)
tmp = char[0] | 0x20
self.header.append(tmp)
else:
self.header.append(char[0])
if len(self.header) == 3 and self.header[2] == 80:
# openDAQ sent a stop command
ret = self.ser.read(2)
char, ch = struct.unpack('!BB', ret)
channel.append(ch - 1)
return 3
self.data_length = self.header[3] - 4
while len(self.data) < self.data_length:
ret = self.ser.read(1)
char = struct.unpack('!B', ret)
if char[0] == 0x7D:
ret = self.ser.read(1)
char = struct.unpack('!B', ret)
tmp = char[0] | 0x20
self.data.append(tmp)
else:
self.data.append(char[0])
for i in range(0, self.data_length, 2):
value = (self.data[i] << 8) | self.data[i + 1]
if value >= 32768:
value -= 65536
data.append(int(value))
channel.append(self.header[4] - 1)
check_stream_crc(self.header, self.data)
return 1
def is_measuring(self):
"""
Returns True if any experiment is going on
"""
return self.__measuring
def start(self):
"""
Start all available experiments
"""
for s in self.experiments:
if s.__class__ is DAQBurst:
self.__create_burst(s.period)
elif s.__class__ is DAQStream:
self.__create_stream(s.number, s.period)
else: # External
self.__create_external(s.number, s.edge)
self.__setup_channel(s.number, s.npoints, s.continuous)
self.__conf_channel(s.number, s.mode, s.pinput, s.ninput, s.gain,
s.nsamples)
if (s.get_mode() == ANALOG_OUTPUT):
pr_data, pr_offset = s.get_preload_data()
for i in range(len(pr_offset)):
self.__load_signal(pr_offset[i], pr_data[i])
break
self.send_command(mkcmd(64, ''), '')
if not self.__running:
threading.Thread.start(self)
self.__running = True
self.__measuring = True
def stop(self):
"""
Stop all running experiments and exit threads.
Experiments will no longer be available.
Call just before quitting program!
Clears experiment list
"""
self.__measuring = False
self.__running = False
self.__stopping = True
while True:
try:
self.send_command(mkcmd(80, ''), '')
self.clear_experiments()
break
except CRCError:
time.sleep(0.2)
self.flush()
def halt(self, clear=False):
"""
Stop running experiments but keep threads active
to start new experiments
Args:
clear - Clear experiment list
"""
self.__measuring = False
while True:
try:
self.send_command(mkcmd(80, ''), '')
time.sleep(1)
break
except CRCError:
time.sleep(0.2)
self.flush()
if clear:
self.clear_experiments()
def run(self):
"""
Thread code.
The procedure stores the experiment data automatically sent
from the device after start()
"""
while True:
while self.__running:
if self.__measuring:
data = []
channel = []
result = self.get_stream(data, channel)
if result == 1:
# data available
available, used = self.dchanindex()
for i in range(len(channel)):
whichexp = used.index(channel[i] + 1)
self.experiments[whichexp].add_point(
self.__raw_to_volts(data[i], whichexp))
elif result == 3:
self.halt()
else:
time.sleep(0.2)
if self.__stopping:
break
class DAQ(threading.Thread):
def __init__(self, port, debug=False):
"""Class constructor"""
threading.Thread.__init__(self)
self.port = port
self.debug = debug
self.simulate = (port == 'sim')
self.__running = False
self.__measuring = False
self.__stopping = False
self.gain = 0
self.pinput = 1
self.open()
info = self.get_info()
self.__fw_ver = info[1]
self.__hw_ver = 'm' if info[0] == 1 else 's'
self.gains, self.offsets = self.get_cal()
self.dac_gain, self.dac_offset = self.get_dac_cal()
self.experiments = []
self.preload_data = None
def open(self):
"""Open the serial port
Configure serial port to be opened."""
if self.simulate:
self.ser = DAQSimulator(self.port, BAUDS, timeout=1)
else:
self.ser = serial.Serial(self.port, BAUDS, timeout=1)
self.ser.setRTS(0)
time.sleep(2)
def close(self):
"""Close the serial port"""
self.ser.close()
def send_command(self, command, ret_fmt):
"""Build a command packet, send it to the openDAQ and process the
response
Args:
cmd: Command string
ret_fmt: Payload format of the response using python
'struct' format characters
Returns:
Command ID and arguments of the response
Raises:
LengthError: The legth of the response is not the expected
"""
fmt = '!BB' + ret_fmt
ret_len = 2 + struct.calcsize(fmt)
self.ser.write(command)
ret = self.ser.read(ret_len)
if self.debug:
print 'Command: ',
for c in command:
print '%02X' % ord(c),
print
print 'Response: ',
for c in ret:
print '%02X' % ord(c),
print
if ret == NAK:
raise IOError("NAK response received")
data = struct.unpack(fmt, check_crc(ret))
if len(ret) != ret_len:
raise LengthError("Bad packet length %d (it should be %d)" %
(len(ret), ret_len))
if data[1] != ret_len-4:
raise LengthError("Bad body length %d (it should be %d)" %
(ret_len-4, data[1]))
# Strip 'command' and 'length' values from returned data
return data[2:]
def get_info(self):
"""Read device configuration
Returns:
[hardware version, firmware version, device ID number]
"""
return self.send_command(mkcmd(39, ''), 'BBI')
def device_info(self):
"""Return device configuration
Returns:
[hardware version, firmware version, device ID number]
"""
hv, fv, serial = self.get_info()
print "Hardware Version: ", "[M]" if hv == 1 else "[S]"
print "Firmware Version:", fv
print "Serial number: OD" + ("M08" if hv == 1
else "S08") + str(serial).zfill(3) + "5"
def hw_ver(self):
return self.__hw_ver
def fw_ver(self):
return self.__fw_ver
def read_adc(self):
"""Read data from ADC and return the raw value
Returns:
Raw ADC value
"""
return self.send_command(mkcmd(1, ''), 'h')[0]
def read_analog(self):
"""Read data from ADC in volts
Returns:
Voltage value
"""
value = self.send_command(mkcmd(1, ''), 'h')[0]
# Raw value to voltage->
index = self.gain + 1 if self.__hw_ver == 'm' else self.pinput
value *= self.gains[index]
value = -value/1e5 if self.__hw_ver == 'm' else value/1e4
value = (value + self.offsets[index])/1e3
return value
def read_all(self, nsamples=20, gain=0):
"""Read data from all analog inputs
Args:
nsamples: Number of samples per data point [0-255] (default=20)
gain: Analog gain
openDAQ[M]= [0:4] (x1/3, x1, x2, x10, x100)
openDAQ[S]= [0:7] (x1,x2,x4,x5,x8,x10,x16,x20)
(default=1)
Returns:
Values[0:7]: List of the analog reading on each input
"""
if self.fw_ver() < 120:
raise Warning("Function not implemented in this FW. Try updating")
self.gain = gain
values = self.send_command(mkcmd(4, 'BB', nsamples, gain), '8h')
if self.__hw_ver == 'm':
a = -self.gains[self.gain + 1]/1e5
b = self.offsets[self.gain + 1]
val = [(v*a+b)/1e3 for v in values]
else:
val = [(v*self.gains[i+1]/1e4+self.offsets[i+1])/1e3
for i, v in enumerate(values)]
return val
def conf_adc(self, pinput=8, ninput=0, gain=0, nsamples=20):
"""
Configure the analog-to-digital converter.
Get the parameters for configure the analog-to-digital
converter.
Args:
pinput: Positive input [1:8]
ninput: Negative input
openDAQ[M]= [0, 5, 6, 7, 8, 25]
openDAQ[S]= [0,1:8] (must be 0 or pinput-1)
gain: Analog gain
openDAQ[M]= [0:4] (x1/3, x1, x2, x10, x100)
openDAQ[S]= [0:7] (x1,x2,x4,x5,x8,x10,x16,x20)
nsamples: Number of samples per data point [0-255)
Raises:
ValueError: Values out of range
"""
if not 1 <= pinput <= 8:
raise ValueError("positive input out of range")
if self.__hw_ver == 'm' and ninput not in [0, 5, 6, 7, 8, 25]:
raise ValueError("negative input out of range")
if self.__hw_ver == 's' and ninput != 0 and (
pinput % 2 == 0 and ninput != pinput - 1 or
pinput % 2 != 0 and ninput != pinput + 1):
raise ValueError("negative input out of range")
if self.__hw_ver == 'm' and not 0 <= gain <= 4:
raise ValueError("gain out of range")
if self.__hw_ver == 's' and not 0 <= gain <= 7:
raise ValueError("gain out of range")
if not 0 <= nsamples < 255:
raise ValueError("samples number out of range")
self.gain = gain
if self.__hw_ver == 's' and ninput != 0:
self.pinput = (pinput - 1)/2 + 9
else:
self.pinput = pinput
return self.send_command(mkcmd(2, 'BBBB', pinput,
ninput, gain, nsamples), 'hBBBB')
def enable_crc(self, on):
"""Enable/Disable the cyclic redundancy check
Args:
on: Enable CRC
Raises:
ValueError: on value out of range
"""
if on not in [0, 1]:
raise ValueError("on value out of range")
return self.send_command(mkcmd(55, 'B', on), 'B')[0]
def set_led(self, color):
"""Choose LED status.
LED switch on (green, red or orange) or switch off.
Args:
color: LED color (0:off, 1:green, 2:red, 3:orange)
Raises:
ValueError: Invalid color number
"""
if not 0 <= color <= 3:
raise ValueError('Invalid color number')
return self.send_command(mkcmd(18, 'B', color), 'B')[0]
def __volts_to_raw(self, volts):
"""Convert a value in volts to a raw value.
Device calibration values are used for the calculation.
openDAQ[M] range: -4.096 V to +4.096 V
openDAQ[S] range: 0 V to +4.096 V
Args:
volts: value to convert to raw
Returns:
Raw value
Raises:
ValueError: DAC voltage out of range
"""
value = int(round(volts*1000))
if self.__hw_ver == 'm' and not -4096 <= value < 4096:
raise ValueError('DAC voltage out of range')
elif self.__hw_ver == 's' and not 0 <= value < 4096:
raise ValueError('DAC voltage out of range')
data = 2*(value * self.dac_gain/1000.0 + self.dac_offset + 4096)
if self.__hw_ver == 's':
data = max(0, min(data, 65535)) # clamp value
return data
def set_analog(self, volts):
"""Set DAC output voltage (millivolts value).
Set the output voltage value between the voltage hardware limits.
Device calibration values are used for the calculation.
openDAQ[M] range: -4.096 V to +4.096 V
openDAQ[S] range: 0 V to +4.096 V
Args:
volts: New DAC output value in millivolts
Raises:
ValueError: DAC voltage out of range
"""
if self.__hw_ver == 'm' and not -4096 <= volts < 4096:
raise ValueError('DAC voltage out of range')
elif self.__hw_ver == 's' and not 0 <= volts < 4096:
raise ValueError('DAC voltage out of range')
data = self.__volts_to_raw(volts)
self.set_dac(data)
def set_dac(self, raw):
"""Set DAC output (binary value)
Set the raw value into DAC without data conversion.
Args:
raw: RAW binary ADC data value.
Raises:
ValueError: DAC voltage out of range
"""
value = int(round(raw))
if (self. __hw_ver == 'm' and not 0 <= value < 16384) or (
self. __hw_ver == 's' and not 0 <= value < 65536):
raise ValueError('DAC value out of range')
return self.send_command(mkcmd(24, 'H', value), 'h')[0]
def set_port_dir(self, output):
"""Configure all PIOs directions.
Set the direction of all D1-D6 terminals.
Args:
output: Port directions byte (bits: 0:input, 1:output)
Raises:
ValueError: output value out of range
"""
if not 0 <= output < 64:
raise ValueError("output value out of range")
return self.send_command(mkcmd(9, 'B', output), 'B')[0]
def set_port(self, value):
"""Write all PIO values
Set the value of all D1-D6 terminals.
Args:
value: Port output byte (bits: 0:low, 1:high)
Returns:
Real value of the port. Output pin as fixed in value\
input pin refresh with current state.
Raises:
ValueError: port output byte out of range
"""
if not 0 <= value < 64:
raise ValueError("port output byte out of range")
return self.send_command(mkcmd(7, 'B', value), 'B')[0]
def set_pio_dir(self, number, output):
"""Configure PIO direction
Set the direction of a specific PIO terminal (D1-D6).
Args:
number: PIO number [1:6]
output: PIO direction (0 input, 1 output)
Raises:
ValueError: Invalid PIO number
"""
if not 1 <= number <= 6:
raise ValueError('Invalid PIO number')
if output not in [0, 1]:
raise ValueError("PIO direction out of range")
return self.send_command(mkcmd(5, 'BB', number,
int(bool(output))), 'BB')
def set_pio(self, number, value):
"""Write PIO output value
Set the value of the PIO terminal (0: low, 1: high).
Args:
number: PIO number (1-6)
value: digital value (0: low, 1: high)
Raises:
ValueError: Invalid PIO number
"""
if not 1 <= number <= 6:
raise ValueError('Invalid PIO number')
if value not in [0, 1]:
raise ValueError("digital value out of range")
return self.send_command(mkcmd(3, 'BB', number,
int(bool(value))), 'BB')
def init_counter(self, edge):
"""Initialize the edge Counter
Configure which edge increments the count:
Low-to-High (1) or High-to-Low (0).
Args:
edge: high-to-low (0) or low-to-high (1)
Raises:
ValueError: edge value out of range
"""
if edge not in [0, 1]:
raise ValueError("edge value out of range")
return self.send_command(mkcmd(41, 'B', edge), 'B')[0]
def get_counter(self, reset):
"""Get the counter value
Args:
reset: reset the counter after perform reading (>0: reset)
Raises:
ValueError: reset value out of range
"""
if not 0 <= reset <= 255:
raise ValueError("reset value out of range")
return self.send_command(mkcmd(42, 'B', reset), 'H')[0]
def init_capture(self, period):
"""Start Capture mode around a given period
Args:
period: estimated period of the wave (in microseconds)
Raises:
ValueError: period out of range
"""
if not 0 <= period <= 65535:
raise ValueError("period out of range")
return self.send_command(mkcmd(14, 'H', period), 'H')[0]
def stop_capture(self):
"""Stop Capture mode
"""
self.send_command(mkcmd(15, ''), '')
def get_capture(self, mode):
"""Get Capture reading for the period length
Low cycle, High cycle or Full period.
Args:
mode: Period length
0: Low cycle
1: High cycle
2: Full period
Returns:
mode
Period: The period length in microseconds
Raises:
ValueError: mode value out of range
"""
if mode not in [0, 1, 2]:
raise ValueError("mode value out of range")
return self.send_command(mkcmd(16, 'B', mode), 'BH')
def init_encoder(self, resolution):
"""Start Encoder function
Args:
resolution: Maximum number of ticks per round [0:65535]
Raises:
ValueError: resolution value out of range
"""
if not 0 <= resolution <= 65535:
raise ValueError("resolution value out of range")
return self.send_command(mkcmd(50, 'B', resolution), 'B')[0]
def get_encoder(self):
"""Get current encoder relative position
Returns:
Position: The actual encoder value.
"""
return self.send_command(mkcmd(52, ''), 'H')[0]
def stop_encoder(self):
"""Stop encoder"""
self.send_command(mkcmd(51, ''), '')
def init_pwm(self, duty, period):
"""Start PWM output with a given period and duty cycle
Args:
duty: High time of the signal [0:1023](0 always low,\
1023 always high)
period: Period of the signal (microseconds) [0:65535]
Raises:
ValueError: Values out of range
"""
if not 0 <= duty < 1024:
raise ValueError("duty value out of range")
if not 0 <= period <= 65535:
raise ValueError("period value out of range")
return self.send_command(mkcmd(10, 'HH', duty, period), 'HH')
def stop_pwm(self):
"""Stop PWM"""
self.send_command(mkcmd(11, ''), '')
def __get_calibration(self, gain_id):
"""
Read device calibration for a given analog configuration
Gets calibration gain and offset for the corresponding analog
configuration
Args:
gain_id: analog configuration
(0:5 for openDAQ [M])
(0:16 for openDAQ [S])
Returns:
gain_id
Gain (x100000[M] or x10000[S])
Offset
Raises:
ValueError: gain_id out of range
"""
if (self.__hw_ver == 'm' and not 0 <= gain_id <= 5) or (
self.__hw_ver == 's' and not 0 <= gain_id <= 16):
raise ValueError("gain_id out of range")
return self.send_command(mkcmd(36, 'B', gain_id), 'BHh')
def get_cal(self):
"""
Read device calibration
Gets calibration values for all the available device configurations
Returns:
Gains
Offsets
"""
gains = []
offsets = []
_range = 6 if self.__hw_ver == "m" else 17
for i in range(_range):
gain_id, gain, offset = self.__get_calibration(i)
gains.append(gain)
offsets.append(offset)
return gains, offsets
def get_dac_cal(self):
"""
Read DAC calibration
Returns:
DAC gain
DAC offset
"""
gain_id, gain, offset = self.__get_calibration(0)
return gain, offset
def __set_calibration(self, gain_id, gain, offset):
"""
Set device calibration
Args:
gain_id: ID of the analog configuration setup
gain: Gain multiplied by 100000 ([M]) or 10000 ([S])
offset: Offset raw value (-32768 to 32768)
Raises:
ValueError: Values out of range
"""
if (self.__hw_ver == 'm' and not 0 <= gain_id <= 5) or (
self.__hw_ver == 's' and not 0 <= gain_id <= 16):
raise ValueError("gain_id out of range")
if not 0 <= gain < 65536:
raise ValueError("gain out of range")
if not -32768 <= offset < 32768:
raise ValueError("offset out of range")
return self.send_command(mkcmd(37, 'BHh', gain_id,
gain, offset), 'BHh')
def set_cal(self, gains, offsets, flag):
"""
Set device calibration
Args:
gains: Gain multiplied by 100000 ([M]) or 10000 ([S])
offsets: Offset raw value (-32768 to 32768)
flag: 'M', 'SE' or 'DE'
Raises:
ValueError: Values out of range
"""
for gain in gains:
if not 0 <= gain < 65536:
raise ValueError("gain out of range")
for offset in offsets:
if not -32768 <= offset < 32768:
raise ValueError("offset out of range")
if flag == 'M':
for i in range(1, 6):
self.__set_calibration(i, gains[i-1], offsets[i-1])
elif flag == 'SE':
for i in range(1, 9):
self.__set_calibration(i, gains[i-1], offsets[i-1])
elif flag == 'DE':
for i in range(9, 17):
self.__set_calibration(i, gains[i-9], offsets[i-9])
else:
raise ValueError("Invalid flag")
def set_dac_cal(self, gain, offset):
"""
Set DAC calibration
Args:
gain: Gain multiplied by 100000 ([M]) or 10000 ([S])
ofset: Offset raw value (-32768 to 32678)
Raises:
ValueError: Values out of range
"""
if not 0 <= gain < 65536:
raise ValueError("gain out of range")
if not -32768 <= offset < 32768:
raise ValueError("offset out of range")
self.__set_calibration(0, gain, offset)
def __raw_to_volts(self, raw, experiment):
"""Convert a raw value to a value in volts.
Args:
raw: Value to convert to volts
experiment: DataChannel number of this experiment
"""
if not 0 <= experiment <= 3:
raise ValueError('Invalid experiment number')
gain_id, pinput, ninput, number = (
self.experiments[experiment].get_parameters())
if self.__hw_ver == 'm':
gain = self.gains[gain_id + 1]
offset = self.offsets[gain_id + 1]
volts = float(raw)
volts *= gain
volts = -volts/1e5
volts = (volts + offset)/1e3
if self.__hw_ver == 's':
n = pinput
if ninput != 0:
n += 8
gain = self.gains[n]
offset = self.offsets[n]
volts = ((float(raw * gain))/1e4 + offset)
volts /= MULTIPLIER_LIST[gain_id]
volts /= 1000.0
return volts
def set_id(self, id):
"""
Identify openDAQ device
Args:
id: id number of the device [000:999]
Raises:
ValueError: id out of range
"""
if not 0 <= id < 1000:
raise ValueError('id out of range')
return self.send_command(mkcmd(39, 'I', id), 'bbI')
def spi_config(self, cpol, cpha):
"""Bit-Bang SPI configure (clock properties)
Args:
cpol: Clock polarity (clock pin state when inactive)
cpha: Clock phase (leading 0, or trailing 1 edges read)
Raises:
ValueError: Invalid spisw_config values
"""
if not 0 <= cpol <= 1 or not 0 <= cpha <= 1:
raise ValueError('Invalid spisw_config values')
return self.send_command(mkcmd(26, 'BB', cpol, cpha), 'BB')
def spi_setup(self, nbytes, sck=1, mosi=2, miso=3):
"""Bit-Bang SPI setup (PIO numbers to use)
Args:
nbytes: Number of bytes
sck: Clock pin
mosi: MOSI pin (master out / slave in)
miso: MISO pin (master in / slave out)
Raises:
ValueError: Invalid values
"""
if not 0 <= nbytes <= 3:
raise ValueError('Invalid number of bytes')
if not 1 <= sck <= 6 or not 1 <= mosi <= 6 or not 1 <= miso <= 6:
raise ValueError('Invalid spisw_setup values')
return self.send_command(mkcmd(28, 'BBB', sck, mosi, miso), 'BBB')
def spi_write(self, value, word=False):
"""Bit-bang SPI transfer (send+receive) a byte or a word
Args:
value: Data to send (byte/word to transmit)
word: send a 2-byte word, instead of a byte
Raises:
ValueError: Value out of range
"""
if not 0 <= value <= 65535:
raise ValueError("value out of range")
if word:
ret = self.send_command(mkcmd(29, 'H', value), 'H')[0]
else:
ret = self.send_command(mkcmd(29, 'B', value), 'B')[0]
return ret
def __conf_channel(
self, number, mode, pinput=1, ninput=0, gain=1, nsamples=1):
"""
Configure a channel for a generic stream experiment.
(Stream/External/Burst).
Args:
- number: Select a DataChannel number for this experiment
- mode: Define data source or destination [0:5]:
0) ANALOG_INPUT
1) ANALOG_OUTPUT
2) DIGITAL_INPUT
3) DIGITAL_OUTPUT
4) COUNTER_INPUT
5) CAPTURE_INPUT
- pinput: Select Positive/SE analog input [1:8]
- ninput: Select Negative analog input:
openDAQ[M]= [0, 5, 6, 7, 8, 25]
openDAQ[S]= [0,1:8] (must be 0 or pinput-1)
- gain: Select PGA multiplier.
In case of openDAQ [M]:
0. x1/2
1. x1
2. x2
3. x10
4. x100
In case of openDAQ [S]:
0. x1
1. x2
2. x4
3. x5
4. x8
5. x10
6. x16
7. x20
- nsamples: Number of samples to calculate the mean for each point\
[0:255].
Raises:
ValueError: Values out of range
"""
if not 1 <= number <= 4:
raise ValueError('Invalid number')
if type(mode) == int and not 0 <= mode <= 5:
raise ValueError('Invalid mode')
if type(mode) == str:
if mode in INPUT_MODES:
mode = INPUT_MODES.index(mode)
else:
raise ValueError('Invalid mode')
if not 0 <= pinput <= 8:
raise ValueError('pinput out of range')
if self.__hw_ver == 'm' and ninput not in [0, 5, 6, 7, 8, 25]:
raise ValueError("negative input out of range")
if self.__hw_ver == 's' and ninput != 0 and (
pinput % 2 == 0 and ninput != pinput - 1 or
pinput % 2 != 0 and ninput != pinput + 1):
raise ValueError("negative input out of range")
if self.__hw_ver == 'm' and not 0 <= gain <= 4:
raise ValueError("gain out of range")
if self.__hw_ver == 's' and not 0 <= gain <= 7:
raise ValueError("gain out of range")
if not 0 <= nsamples < 255:
raise ValueError("samples number out of range")
return self.send_command(mkcmd(22, 'BBBBBB', number, mode, pinput,
ninput, gain, nsamples), 'BBBBBB')
def __setup_channel(self, number, npoints, continuous=False):
"""
Configure the experiment's number of points
Args:
number: Select a DataChannel number for this experiment
npoints: Total number of points for the experiment
[0:65536] (0 indicates continuous acquisition)
continuous: Indicates if experiment is continuous
False run once
True continuous
Raises:
ValueError: Values out of range
"""
if not 1 <= number <= 4:
raise ValueError('Invalid number')
if not 0 <= npoints < 65536:
raise ValueError('npoints out of range')
return self.send_command(mkcmd(32, 'BHb', number,
npoints, int(not continuous)), 'BHB')
def remove_experiment(self, experiment):
"""
Delete a single experiment
Args:
experiment: reference of the experiment to remove
Raises:
ValueError: Invalid reference
"""
nb = experiment.get_parameters()[3]
if not 1 <= nb <= 4:
raise ValueError('Invalid reference')
self.__destroy_channel(nb)
for i in range(len(self.experiments))[::-1]:
if self.experiments[i].number == nb:
del(self.experiments[i])
def clear_experiments(self):
"""
Delete the whole experiment list
Args:
None
"""
for i in range(len(self.experiments))[::-1]:
self.__destroy_channel(i+1)
del(self.experiments[i])
def dchanindex(self):
"""
Check which internal DataChannels are used or available
Args:
None
Returns:
available: list of free DataChannels
used: list of asigned DataChannels
"""
used = [e.number for e in self.experiments]
available = [i for i in range(1, 5) if i not in used]
return available, used
def __destroy_channel(self, number):
"""
Command firmware to clear a Datachannel structure
Args:
number: Number of DataChannel structure to clear
[0:4] (0: reset all DataChannels)
Raises:
ValueError: Invalid number
"""
if not 1 <= number <= 4:
raise ValueError('Invalid number')
return self.send_command(mkcmd(57, 'B', number), 'B')[0]
def create_stream(self, mode, *args, **kwargs):
"""
Create Stream experiment
See class constructor for more info
"""
available, used = self.dchanindex()
index = len(self.experiments)
if index > 0 and self.experiments[0].__class__ is DAQBurst:
raise LengthError('Device is configured for a Burst experiment')
if len(available) == 0:
raise LengthError('Only 4 experiments available at a time')
if mode == ANALOG_OUTPUT:
chan = 4 # DAC_OUTPUT is fixed at DataChannel 4
for i in range(index):
if self.experiments[i].number == chan:
if type(self.experiments[i]) is DAQStream:
self.experiments[i].number = available[0]
else:
raise ValueError('DataChannel 4 is being used')
else:
chan = available[0]
self.experiments.append(DAQStream(mode, chan, *args, **kwargs))
return self.experiments[index]
def __create_stream(self, number, period):
"""
Send a command to the firmware to create Stream experiment
Args:
number: Assign a DataChannel number for this experiment [1:4]
period: Period of the stream experiment
(milliseconds) [1:65536]
Raises:
ValueError: Invalid values
"""
if not 1 <= number <= 4:
raise ValueError('Invalid number')
if not 1 <= period <= 65535:
raise ValueError('Invalid period')
return self.send_command(mkcmd(19, 'BH', number, period), 'BH')
def create_external(self, mode, clock_input, *args, **kwargs):
"""
Create External experiment
See class constructor for more info
"""
available, used = self.dchanindex()
index = len(self.experiments)
if index > 0 and self.experiments[0].__class__ is DAQBurst:
raise LengthError('Device is configured for a Burst experiment')
if len(available) == 0:
raise LengthError('Only 4 experiments available at a time')
for i in range(index):
if self.experiments[i].number == clock_input:
if type(self.experiments[i]) is DAQStream:
self.experiments[i].number = available[0]
else:
raise ValueError(
'Clock_input is being used by another experiment')
self.experiments.append(DAQExternal(mode, clock_input,
*args, **kwargs))
return self.experiments[index]
def __create_external(self, number, edge):
"""
Send a command to the firmware to create External experiment
Args:
number: Assign a DataChannel number for this experiment [1:4]
edge: New data on rising (1) or falling (0) edges [0:1]
Raises:
ValueError: Invalid values
"""
if not 1 <= number <= 4:
raise ValueError('Invalid number')
if edge not in [0, 1]:
raise ValueError('Invalid edge')
return self.send_command(mkcmd(20, 'BB', number, edge), 'BB')
def create_burst(self, *args, **kwargs):
"""
Create Burst experiment
"""
if len(self.experiments) > 0:
raise ValueError(
'Only 1 experiment available at a time if using burst')
self.experiments.append(DAQBurst(*args, **kwargs))
return self.experiments[0]
def __create_burst(self, period):
"""
Send a command to the firmware to create Burst experiment
Args:
period: Period of the burst experiment
(microseconds) [100:65535]
Raises:
ValueError: Invalid period
"""
if not 100 <= period <= 65535:
raise ValueError('Invalid period')
return self.send_command(mkcmd(21, 'H', period), 'H')
def __load_signal(self, pr_of, pr_data):
"""
Load an array of values in volts to preload DAC output
Raises:
LengthError: Invalid dada length
"""
if not 1 <= len(pr_data) <= 400:
raise LengthError('Invalid data length')
values = []
self.set_analog(pr_data[0])
for volts in pr_data:
raw = self.__volts_to_raw(volts)
'''
if self.__hw_ver == "s":
raw *= 2
'''
values.append(raw)
return self.send_command(mkcmd(23, 'h%dH' % len(values),
pr_of, *values), 'Bh')
def flush(self):
"""
Flush internal buffers
"""
self.ser.flushInput()
def get_stream(self, data, channel):
"""
Serial parser.
Low-level function for stream data collecting.
Args:
data: Buffer for data points
channel: Buffer for assigned experiment number
Returns:
0 if there is not any incoming data.
1 if data stream was processed.
2 if no data stream received.
"""
self.header = []
self.data = []
ret = self.ser.read(1)
if not ret:
return 0
head = struct.unpack('!b', ret)
if head[0] != 0x7E:
data.append(head[0])
return 2
# Get header
while len(self.header) < 8:
ret = self.ser.read(1)
char = struct.unpack('!B', ret)
if char[0] == 0x7D:
ret = self.ser.read(1)
char = struct.unpack('!B', ret)
tmp = char[0] | 0x20
self.header.append(tmp)
else:
self.header.append(char[0])
if len(self.header) == 3 and self.header[2] == 80:
# openDAQ sent a stop command
ret = self.ser.read(2)
char, ch = struct.unpack('!BB', ret)
channel.append(ch-1)
return 3
self.data_length = self.header[3] - 4
while len(self.data) < self.data_length:
ret = self.ser.read(1)
char = struct.unpack('!B', ret)
if char[0] == 0x7D:
ret = self.ser.read(1)
char = struct.unpack('!B', ret)
tmp = char[0] | 0x20
self.data.append(tmp)
else:
self.data.append(char[0])
for i in range(0, self.data_length, 2):
value = (self.data[i] << 8) | self.data[i+1]
if value >= 32768:
value -= 65536
data.append(int(value))
channel.append(self.header[4]-1)
check_stream_crc(self.header, self.data)
return 1
def is_measuring(self):
"""
Returns True if any experiment is going on
"""
return self.__measuring
def start(self):
"""
Start all available experiments
"""
for s in self.experiments:
if s.__class__ is DAQBurst:
self.__create_burst(s.period)
elif s.__class__ is DAQStream:
self.__create_stream(s.number, s.period)
else: # External
self.__create_external(s.number, s.edge)
self.__setup_channel(s.number, s.npoints, s.continuous)
self.__conf_channel(s.number, s.mode, s.pinput,
s.ninput, s.gain, s.nsamples)
if (s.get_mode() == ANALOG_OUTPUT):
pr_data, pr_offset = s.get_preload_data()
for i in range(len(pr_offset)):
self.__load_signal(pr_offset[i], pr_data[i])
break
self.send_command(mkcmd(64, ''), '')
if not self.__running:
threading.Thread.start(self)
self.__running = True
self.__measuring = True
def stop(self):
"""
Stop all running experiments and exit threads.
Experiments will no longer be available.
Call just before quitting program!
Clears experiment list
"""
self.__measuring = False
self.__running = False
self.__stopping = True
while True:
try:
self.send_command(mkcmd(80, ''), '')
self.clear_experiments()
break
except CRCError:
time.sleep(0.2)
self.flush()
def halt(self, clear=False):
"""
Stop running experiments but keep threads active
to start new experiments
Args:
clear - Clear experiment list
"""
self.__measuring = False
while True:
try:
self.send_command(mkcmd(80, ''), '')
time.sleep(1)
break
except CRCError:
time.sleep(0.2)
self.flush()
if clear:
self.clear_experiments()
def run(self):
"""
Thread code.
The procedure stores the experiment data automatically sent
from the device after start()
"""
while True:
while self.__running:
if self.__measuring:
data = []
channel = []
result = self.get_stream(data, channel)
if result == 1:
# data available
available, used = self.dchanindex()
for i in range(len(channel)):
whichexp = used.index(channel[i]+1)
self.experiments[whichexp].add_point(
self.__raw_to_volts(data[i], whichexp))
elif result == 3:
self.halt()
else:
time.sleep(0.2)
if self.__stopping:
break
def setUp(self):
self.daq = DAQSimulator()
class DAQ:
def __init__(self, port, debug=False):
"""Class constructor"""
self.port = port
self.debug = debug
self.simulate = (port == 'sim')
self.measuring = False
self.gain = 0
self.pinput = 1
self.open()
info = self.get_info()
self.hw_ver = 'm' if info[0] == 1 else 's'
self.gains, self.offsets = self.get_cal()
self.dac_gain, self.dac_offset = self.get_dac_cal()
def open(self):
"""Open the serial port
Configure serial port to be opened."""
if self.simulate:
self.ser = DAQSimulator(self.port, BAUDS, timeout=1)
else:
self.ser = serial.Serial(self.port, BAUDS, timeout=1)
self.ser.setRTS(0)
time.sleep(2)
def close(self):
"""Close the serial port"""
self.ser.close()
def send_command(self, cmd, ret_fmt):
"""Build a command packet, send it to the openDAQ and process the
response
Args:
cmd: Command ID
ret_fmt: Payload format using python 'struct' format characters
Returns:
Command ID and arguments of the response
Raises:
LengthError: The legth of the response is not the expected
"""
if self.measuring:
self.stop()
# Add 'command' and 'length' fields to the format string
fmt = '!BB' + ret_fmt
ret_len = 2 + struct.calcsize(fmt)
packet = crc(cmd) + cmd
self.ser.write(packet)
ret = self.ser.read(ret_len)
if self.debug:
print 'Command: ',
for c in packet:
print '%02X' % ord(c),
print
print 'Response: ',
for c in ret:
print '%02X' % ord(c),
print
if ret == NAK:
raise IOError("NAK response received")
data = struct.unpack(fmt, check_crc(ret))
if len(ret) != ret_len:
raise LengthError("Bad packet length %d (it should be %d)" %
(len(ret), ret_len))
if data[1] != ret_len-4:
raise LengthError("Bad body length %d (it should be %d)" %
(ret_len-4, data[1]))
# Strip 'command' and 'length' values from returned data
return data[2:]
def get_info(self):
"""Read device configuration
Returns:
[hardware version, firmware version, device ID number]
"""
return self.send_command('\x27\x00', 'BBI')
def read_adc(self):
"""Read data from ADC and return the raw value
Returns:
Raw ADC value
"""
value = self.send_command('\x01\x00', 'h')[0]
return value
def read_analog(self):
"""Read data from ADC in volts
Returns:
Voltage value
"""
value = self.send_command('\x01\x00', 'h')[0]
# Raw value to voltage->
index = self.gain + 1 if self.hw_ver == 'm' else self.pinput
value *= self.gains[index]
value = -value/1e5 if self.hw_ver == 'm' else value/1e4
value = (value + self.offsets[index])/1e3
return value
def conf_adc(self, pinput, ninput=0, gain=0, nsamples=20):
""" Configure the analog-to-digital converter.
Get the parameters for configure the analog-to-digital
converter.
Args:
pinput: Positive input [1:8]
ninput: Negative input
openDAQ[M]= [0, 5, 6, 7, 8, 25]
openDAQ[S]= [0,1:8] (must be 0 or pinput-1)
gain: Analog gain
openDAQ[M]= [0:4] (x1/3, x1, x2, x10, x100)
openDAQ[S]= [0:7] (x1,x2,x4,x5,x8,x10,x16,x20)
nsamples: Number of samples per data point [0-255)
Raises:
ValueError: Values out of range
"""
if not 1 <= pinput <= 8:
raise ValueError("positive input out of range")
if self.hw_ver == 'm' and ninput not in [0, 5, 6, 7, 8, 25]:
raise ValueError("negative input out of range")
if self.hw_ver == 's' and ninput != 0 and (
pinput % 2 == 0 and ninput != pinput - 1
or pinput % 2 != 0 and ninput != pinput + 1):
raise ValueError("negative input out of range")
if self.hw_ver == 'm' and not 0 <= gain <= 4:
raise ValueError("gain out of range")
if self.hw_ver == 's' and not 0 <= gain <= 7:
raise ValueError("gain out of range")
if not 0 <= nsamples < 255:
raise ValueError("samples number out of range")
self.gain = gain
if self.hw_ver == 's' and ninput != 0:
self.pinput = (pinput - 1)/2 + 9
else:
self.pinput = pinput
cmd = struct.pack('!BBBBBB', 2, 4, pinput, ninput, gain, nsamples)
self.send_command(cmd, 'hBBBB')
def enable_crc(self, on):
"""Enable/Disable the cyclic redundancy check
Args:
on: Enable CRC
Raises:
ValueError: on value out of range
"""
if on not in [0, 1]:
raise ValueError("on value out of range")
cmd = struct.pack('!BBB', 55, 1, on)
self.send_command(cmd, 'B')[0]
def set_led(self, color):
"""Choose LED status.
LED switch on (green, red or orange) or switch off.
Args:
color: LED color (0:off, 1:green, 2:red, 3:orange)
Raises:
ValueError: Invalid color number
"""
if not 0 <= color <= 3:
raise ValueError('Invalid color number')
cmd = struct.pack('!BBB', 18, 1, color)
self.send_command(cmd, 'B')[0]
def __volts_to_raw(self, volts):
"""Convert a value in volts to a raw value.
Device calibration values are used for the calculation.
openDAQ[M] range: -4.096 V to +4.096 V
openDAQ[S] range: 0 V to +4.096 V
Args:
volts: value to convert to raw
Returns:
Raw value
Raises:
ValueError: DAC voltage out of range
"""
value = int(round(volts*1000))
if self.hw_ver == 'm' and not -4096 <= value < 4096:
raise ValueError('DAC voltage out of range')
elif self.hw_ver == 's' and not 0 <= value < 4096:
raise ValueError('DAC voltage out of range')
data = 2*(value * self.dac_gain/1000.0 + self.dac_offset + 4096)
if self.hw_ver == 's':
data = max(0, min(data, 65535)) # clamp value
return data
def set_analog(self, volts):
"""Set DAC output voltage (millivolts value).
Set the output voltage value between the voltage hardware limits.
Device calibration values are used for the calculation.
openDAQ[M] range: -4.096 V to +4.096 V
openDAQ[S] range: 0 V to +4.096 V
Args:
volts: New DAC output value in millivolts
Raises:
ValueError: DAC voltage out of range
"""
if self.hw_ver == 'm' and not -4096 <= volts < 4096:
raise ValueError('DAC voltage out of range')
elif self.hw_ver == 's' and not 0 <= volts < 4096:
raise ValueError('DAC voltage out of range')
data = self.__volts_to_raw(volts)
self.set_dac(data)
def set_dac(self, raw):
"""Set DAC output (binary value)
Set the raw value into DAC without data conversion.
Args:
raw: RAW binary ADC data value.
Raises:
ValueError: DAC voltage out of range
"""
value = int(round(raw))
if (self. hw_ver == 'm' and not 0 <= value < 16384) or (
self. hw_ver == 's' and not 0 <= value < 65536):
raise ValueError('DAC value out of range')
cmd = struct.pack('!BBH', 24, 2, value)
self.send_command(cmd, 'h')[0]
def set_port_dir(self, output):
"""Configure all PIOs directions.
Set the direction of all D1-D6 terminals.
Args:
output: Port directions byte (bits: 0:input, 1:output)
Raises:
ValueError: output value out of range
"""
if not 0 <= output < 64:
raise ValueError("output value out of range")
cmd = struct.pack('!BBB', 9, 1, output)
self.send_command(cmd, 'B')[0]
def set_port(self, value):
"""Write all PIO values
Set the value of all D1-D6 terminals.
Args:
value: Port output byte (bits: 0:low, 1:high)
Returns:
Real value of the port. Output pin as fixed in value\
input pin refresh with current state.
Raises:
ValueError: port output byte out of range
"""
if not 0 <= value < 64:
raise ValueError("port output byte out of range")
cmd = struct.pack('!BBB', 7, 1, value)
return self.send_command(cmd, 'B')[0]
def set_pio_dir(self, number, output):
"""Configure PIO direction
Set the direction of a specific PIO terminal (D1-D6).
Args:
number: PIO number [1:6]
output: PIO direction (0 input, 1 output)
Raises:
ValueError: Invalid PIO number
"""
if not 1 <= number <= 6:
raise ValueError('Invalid PIO number')
if output not in [0, 1]:
raise ValueError("PIO direction out of range")
cmd = struct.pack('!BBBB', 5, 2, number, int(bool(output)))
self.send_command(cmd, 'BB')
def set_pio(self, number, value):
"""Write PIO output value
Set the value of the PIO terminal (0: low, 1: high).
Args:
number: PIO number (1-6)
value: digital value (0: low, 1: high)
Raises:
ValueError: Invalid PIO number
"""
if not 1 <= number <= 6:
raise ValueError('Invalid PIO number')
if value not in [0, 1]:
raise ValueError("digital value out of range")
cmd = struct.pack('!BBBB', 3, 2, number, int(bool(value)))
self.send_command(cmd, 'BB')
def init_counter(self, edge):
"""Initialize the edge Counter
Configure which edge increments the count:
Low-to-High (1) or High-to-Low (0).
Args:
edge: high-to-low (0) or low-to-high (1)
Raises:
ValueError: edge value out of range
"""
if edge not in [0, 1]:
raise ValueError("edge value out of range")
cmd = struct.pack('!BBB', 41, 1, edge)
self.send_command(cmd, 'B')[0]
def get_counter(self, reset):
"""Get the counter value
Args:
reset: reset the counter after perform reading (>0: reset)
Raises:
ValueError: reset value out of range
"""
if not 0 <= reset <= 255:
raise ValueError("reset value out of range")
cmd = struct.pack('!BBB', 42, 1, reset)
return self.send_command(cmd, 'H')[0]
def init_capture(self, period):
"""Start Capture mode around a given period
Args:
period: estimated period of the wave (in microseconds)
Raises:
ValueError: period out of range
"""
if not 0 <= period <= 65535:
raise ValueError("period out of range")
cmd = struct.pack('!BBH', 14, 2, period)
return self.send_command(cmd, 'H')[0]
def stop_capture(self):
"""Stop Capture mode
"""
self.send_command('\x0F\x00', '')
def get_capture(self, mode):
"""Get Capture reading for the period length
Low cycle, High cycle or Full period.
Args:
mode: Period length
0: Low cycle
1: High cycle
2: Full period
Returns:
Period: The period length in microseconds
Raises:
ValueError: mode value out of range
"""
if mode not in [0, 1, 2]:
raise ValueError("mode value out of range")
cmd = struct.pack('!BBB', 16, 1, mode)
return self.send_command(cmd, 'BH')
def init_encoder(self, resolution):
"""Start Encoder function
Args:
resolution: Maximum number of ticks per round [0:65535]
Raises:
ValueError: resolution value out of range
"""
if not 0 <= resolution <= 65535:
raise ValueError("resolution value out of range")
cmd = struct.pack('!BBB', 50, 1, resolution)
return self.send_command(cmd, 'B')[0]
def get_encoder(self):
"""Get current encoder relative position
Returns:
Position: The actual encoder value.
"""
return self.send_command('\x34\x00', 'H')
def stop_encoder(self):
"""Stop encoder"""
self.send_command('\x33\x00', '')
def init_pwm(self, duty, period):
"""Start PWM output with a given period and duty cycle
Args:
duty: High time of the signal [0:1023](0 always low,\
1023 always high)
period: Period of the signal (microseconds) [0:65535]
Raises:
ValueError: Values out of range
"""
if not 0 <= duty < 1024:
raise ValueError("duty value out of range")
if not 0 <= period <= 65535:
raise ValueError("period value out of range")
cmd = struct.pack('!BBHH', 10, 4, duty, period)
return self.send_command(cmd, 'HH')
def stop_pwm(self):
"""Stop PWM"""
self.send_command('\x0b\x00', '')
def __get_calibration(self, gain_id):
"""
Read device calibration for a given analog configuration
Gets calibration gain and offset for the corresponding analog
configuration
Args:
gain_id: analog configuration
(0:5 for openDAQ [M])
(0:16 for openDAQ [S])
Returns:
Gain (x100000[M] or x10000[S])
Offset
Raises:
ValueError: gain_id out of range
"""
if (self.hw_ver == 'm' and not 0 <= gain_id <= 5) or (
self.hw_ver == 's' and not 0 <= gain_id <= 16):
raise ValueError("gain_id out of range")
cmd = struct.pack('!BBB', 36, 1, gain_id)
return self.send_command(cmd, 'BHh')
def get_cal(self):
"""
Read device calibration
Gets calibration values for all the available device configurations
Returns:
Gains
Offsets
"""
gains = []
offsets = []
_range = 6 if self.hw_ver == "m" else 17
for i in range(_range):
gain_id, gain, offset = self.__get_calibration(i)
gains.append(gain)
offsets.append(offset)
return gains, offsets
def get_dac_cal(self):
"""
Read DAC calibration
Returns:
DAC gain
DAC offset
"""
gain_id, gain, offset = self.__get_calibration(0)
return gain, offset
def __set_calibration(self, gain_id, gain, offset):
"""
Set device calibration
Args:
gain_id: ID of the analog configuration setup
gain: Gain multiplied by 100000 ([M]) or 10000 ([S])
offset: Offset raw value (-32768 to 32768)
Raises:
ValueError: Values out of range
"""
if (self.hw_ver == 'm' and not 0 <= gain_id <= 5) or (
self.hw_ver == 's' and not 0 <= gain_id <= 16):
raise ValueError("gain_id out of range")
if not 0 <= gain < 65536:
raise ValueError("gain out of range")
if not -32768 <= offset < 32768:
raise ValueError("offset out of range")
cmd = struct.pack('!BBBHh', 37, 5, gain_id, gain, offset)
return self.send_command(cmd, 'BHh')
def set_cal(self, gains, offsets, flag):
"""
Set device calibration
Args:
gains: Gain multiplied by 100000 ([M]) or 10000 ([S])
offsets: Offset raw value (-32768 to 32768)
flag: 'M', 'SE' or 'DE'
Raises:
ValueError: Values out of range
"""
for gain in gains:
if not 0 <= gain < 65536:
raise ValueError("gain out of range")
for offset in offsets:
if not -32768 <= offset < 32768:
raise ValueError("offset out of range")
if flag == 'M':
for i in range(1, 6):
self.__set_calibration(i, gains[i-1], offsets[i-1])
elif flag == 'SE':
for i in range(1, 9):
self.__set_calibration(i, gains[i-1], offsets[i-1])
elif flag == 'DE':
for i in range(9, 17):
self.__set_calibration(i, gains[i-9], offsets[i-9])
else:
raise ValueError("Invalid flag")
def set_dac_cal(self, gain, offset):
"""
Set DAC calibration
Args:
gain: Gain multiplied by 100000 ([M]) or 10000 ([S])
ofset: Offset raw value (-32768 to 32678)
Raises:
ValueError: Values out of range
"""
if not 0 <= gain < 65536:
raise ValueError("gain out of range")
if not -32768 <= offset < 32768:
raise ValueError("offset out of range")
self.__set_calibration(0, gain, offset)
def conf_channel(
self, number, mode, pinput=1, ninput=0, gain=1, nsamples=1):
"""
Configure a channel for a generic stream experiment.
(Stream/External/Burst).
Args:
- number: Select a DataChannel number for this experiment
- mode: Define data source or destination [0:5]:
0) ANALOG_INPUT
1) ANALOG_OUTPUT
2) DIGITAL_INPUT
3) DIGITAL_OUTPUT
4) COUNTER_INPUT
5) CAPTURE INPUT
- pinput: Select Positive/SE analog input [1:8]
- ninput: Select Negative analog input:
openDAQ[M]= [0, 5, 6, 7, 8, 25]
openDAQ[S]= [0,1:8] (must be 0 or pinput-1)
- gain: Select PGA multiplier.
In case of openDAQ [M]:
0. x1/2
1. x1
2. x2
3. x10
4. x100
In case of openDAQ [S]:
0. x1
1. x2
2. x4
3. x5
4. x8
5. x10
6. x16
7. x20
- nsamples: Number of samples to calculate the mean for each point\
[0:255].
Raises:
ValueError: Values out of range
"""
if not 1 <= number <= 4:
raise ValueError('Invalid number')
if type(mode) == int and not 0 <= mode <= 5:
raise ValueError('Invalid mode')
if type(mode) == str:
if mode in INPUT_MODES:
mode = INPUT_MODES.index(mode)
else:
raise ValueError('Invalid mode')
if not 0 <= pinput <= 8:
raise ValueError('pinput out of range')
if self.hw_ver == 'm' and ninput not in [0, 5, 6, 7, 8, 25]:
raise ValueError("negative input out of range")
if self.hw_ver == 's' and ninput != 0 and (
pinput % 2 == 0 and ninput != pinput - 1
or pinput % 2 != 0 and ninput != pinput + 1):
raise ValueError("negative input out of range")
if self.hw_ver == 'm' and not 0 <= gain <= 4:
raise ValueError("gain out of range")
if self.hw_ver == 's' and not 0 <= gain <= 7:
raise ValueError("gain out of range")
if not 0 <= nsamples < 255:
raise ValueError("samples number out of range")
cmd = struct.pack('!BBBBBBBB', 22, 6, number, mode,
pinput, ninput, gain, nsamples)
return self.send_command(cmd, 'BBBBBB')
def setup_channel(self, number, npoints, continuous=True):
"""
Configure the experiment's number of points
Args:
number: Select a DataChannel number for this experiment
npoints: Total number of points for the experiment
[0:65536] (0 indicates continuous acquisition)
continuous: Number of repeats [0:1]
0 continuous
1 run once
Raises:
ValueError: Values out of range
"""
if not 1 <= number <= 4:
raise ValueError('Invalid number')
if not 0 <= npoints < 65536:
raise ValueError('npoints out of range')
if continuous not in [0, 1]:
raise ValueError("continuous value out of range")
cmd = struct.pack('!BBBHb', 32, 4, number, npoints, int(continuous))
return self.send_command(cmd, 'BHB')
def destroy_channel(self, number):
"""
Delete Datachannel structure
Args:
number: Number of DataChannel structure to clear
[0:4] (0: reset all DataChannels)
Raises:
ValueError: Invalid number
"""
if not 1 <= number <= 4:
raise ValueError('Invalid number')
cmd = struct.pack('!BBB', 57, 1, number)
return self.send_command(cmd, 'B')
def create_stream(self, number, period):
"""
Create Stream experiment
Args:
number: Assign a DataChannel number for this experiment [1:4]
period: Period of the stream experiment
(milliseconds) [1:65536]
Raises:
ValueError: Invalid values
"""
if not 1 <= number <= 4:
raise ValueError('Invalid number')
if not 1 <= period <= 65535:
raise ValueError('Invalid period')
cmd = struct.pack('!BBBH', 19, 3, number, period)
return self.send_command(cmd, 'BH')
def create_burst(self, period):
"""
Create Burst experiment
Args:
period: Period of the burst experiment
(microseconds) [100:65535]
Raises:
ValueError: Invalid period
"""
if not 100 <= period <= 65535:
raise ValueError('Invalid period')
cmd = struct.pack('!BBH', 21, 2, period)
return self.send_command(cmd, 'H')
def create_external(self, number, edge):
"""
Create External experiment
Args:
number: Assign a DataChannel number for this experiment [1:4]
edge: New data on rising (1) or falling (0) edges [0:1]
Raises:
ValueError: Invalid values
"""
if not 1 <= number <= 4:
raise ValueError('Invalid number')
if not edge in [0, 1]:
raise ValueError('Invalid edge')
cmd = struct.pack('!BBBB', 20, 2, number, edge)
return self.send_command(cmd, 'BB')
def load_signal(self, data, offset):
"""
Load an array of values in volts to preload DAC output
Args:
data: Total number of data points [1:400]
offset: Offset for each value
Raises:
LengthError: Invalid dada length
"""
if not 1 <= len(data) <= 400:
raise LengthError('Invalid data length')
values = []
for volts in data:
raw = self.__volts_to_raw(volts)
if self.hw_ver == "s":
raw *= 2
values.append(raw)
cmd = struct.pack(
'!bBh%dH' % len(values), 23, len(values) * 2 + 2, offset, *values)
return self.send_command(cmd, 'Bh')
def start(self):
"""
Start all available experiments
"""
self.send_command('\x40\x00', '')
self.measuring = True
def stop(self):
"""
Stop all running experiments
"""
self.measuring = False
while True:
try:
self.send_command('\x50\x00', '')
break
except:
time.sleep(0.2)
self.flush()
def flush(self):
"""
Flush internal buffers
"""
self.ser.flushInput()
def flush_stream(self, data, channel):
"""
Flush stream data from buffer
Args:
data:
channel: Experiment number
Returns:
0 if there is no incoming data.
1 if data stream was processed.
2 if no data stream received. Useful for debugging.
Raises:
LengthError: An error ocurred
"""
if not 1 <= channel <= 4:
raise ValueError('channel out of range')
# Receive all stream data in the in buffer
while 1:
ret = self.ser.read(1)
if not ret:
break
else:
cmd = struct.unpack('!b', ret)
if cmd[0] == 0x7E:
self.header = []
self.data = []
while len(self.header) < 8:
ret = self.ser.read(1)
char = struct.unpack('!B', ret)
if char[0] == 0x7D:
ret = self.ser.read(1)
self.header.append(char[0])
length = self.header[3]
self.data_length = length - 4
while len(self.data) < self.data_length:
ret = self.ser.read(1)
char = struct.unpack('>B', ret)
if char[0] == 0x7D:
ret = self.ser.read(1)
char = struct.unpack('>B', ret)
tmp = char[0] | 0x20
self.data.append(tmp)
else:
self.data.append(char[0])
if check_stream_crc(self.header, self.data) != 1:
continue
for i in range(0, self.data_length, 2):
value = (self.data[i] << 8) | self.data[i+1]
if value >= 32768:
value -= 65536
data.append(int(value))
channel.append(self.header[4]-1)
else:
break
ret = self.ser.read(3)
ret += str(cmd[0])
if len(ret) != 4:
raise LengthError
# This function reads a stream from serial connection
# Returns 0 if there is not incoming data
# Returns 1 if data stream was precessed
# Returns 2 if no data stream was received (useful for debugging)
def get_stream(self, data, channel):
"""Get stream from serial connection
Args:
data: Data buffer
channel: Experiment number
Returns:
0 if there is not any incoming data.
1 if data stream was processed.
2 if no data stream received.
"""
self.header = []
self.data = []
ret = self.ser.read(1)
if not ret:
return 0
head = struct.unpack('!b', ret)
if head[0] != 0x7E:
data.append(head[0])
return 2
# Get header
while len(self.header) < 8:
ret = self.ser.read(1)
char = struct.unpack('!B', ret)
if char[0] == 0x7D:
ret = self.ser.read(1)
char = struct.unpack('!B', ret)
tmp = char[0] | 0x20
self.header.append(tmp)
else:
self.header.append(char[0])
if len(self.header) == 3 and self.header[2] == 80:
# openDAQ sent a stop command
ret = self.ser.read(2)
char, ch = struct.unpack('!BB', ret)
channel.append(ch-1)
return 3
self.data_length = self.header[3] - 4
while len(self.data) < self.data_length:
ret = self.ser.read(1)
char = struct.unpack('!B', ret)
if char[0] == 0x7D:
ret = self.ser.read(1)
char = struct.unpack('!B', ret)
tmp = char[0] | 0x20
self.data.append(tmp)
else:
self.data.append(char[0])
for i in range(0, self.data_length, 2):
value = (self.data[i] << 8) | self.data[i+1]
if value >= 32768:
value -= 65536
data.append(int(value))
check_stream_crc(self.header, self.data)
channel.append(self.header[4]-1)
return 1
def set_id(self, id):
"""
Identify openDAQ device
Args:
id: id number of the device [000:999]
Raises:
ValueError: id out of range
"""
if not 0 <= id < 1000:
raise ValueError('id out of range')
cmd = struct.pack('!BBI', 39, 4, id)
return self.send_command(cmd, 'bbI')
def spi_config(self, cpol, cpha):
"""Bit-Bang SPI configure (clock properties)
Args:
cpol: Clock polarity (clock pin state when inactive)
cpha: Clock phase (leading 0, or trailing 1 edges read)
Raises:
ValueError: Invalid spisw_config values
"""
if not 0 <= cpol <= 1 or not 0 <= cpha <= 1:
raise ValueError('Invalid spisw_config values')
cmd = struct.pack('!BBB', 26, 2, cpol, cpha)
return self.send_command(cmd, 'BB')
def spi_setup(self, nbytes, sck=1, mosi=2, miso=3):
"""Bit-Bang SPI setup (PIO numbers to use)
Args:
nbytes: Number of bytes
sck: Clock pin
mosi: MOSI pin (master out / slave in)
miso: MISO pin (master in / slave out)
Raises:
ValueError: Invalid values
"""
if not 0 <= nbytes <= 3:
raise ValueError('Invalid number of bytes')
if not 1 <= sck <= 6 or not 1 <= mosi <= 6 or not 1 <= miso <= 6:
raise ValueError('Invalid spisw_setup values')
cmd = struct.pack('!BBBBB', 28, 3, sck, mosi, miso)
return self.send_command(cmd, 'BBB')
def spi_write(self, value, word=False):
"""Bit-bang SPI transfer (send+receive) a byte or a word
Args:
value: Data to send (byte/word to transmit)
word: send a 2-byte word, instead of a byte
Raises:
ValueError: Value out of range
"""
if not 0 <= value <= 65535:
raise ValueError("value out of range")
if word:
cmd = struct.pack('!BBH', 29, 2, value)
ret = self.send_command(cmd, 'H')[0]
else:
cmd = struct.pack('!BBB', 29, 1, value)
ret = self.send_command(cmd, 'B')[0]
return ret
