def readLuaInfo(handle):
"""Function that selects the current lua execution block and prints
out associated info from lua
"""
try:
for i in range(20):
# The script sets the interval length with LJ.IntervalConfig.
# Note that LJ.IntervalConfig has some jitter and that this program's
# interval (set by sleep) will have some minor drift from
# LJ.IntervalConfig.
sleep(1)
print("LUA_RUN: %d" % ljm.eReadName(handle, "LUA_RUN"))
# Add custom logic to control the Lua execution block
executionLoopNum = i % 3
# Write which lua control block to run using the user ram register
ljm.eWriteName(handle, "USER_RAM0_U16", executionLoopNum)
numBytes = ljm.eReadName(handle, "LUA_DEBUG_NUM_BYTES")
if (int(numBytes) == 0):
continue
print("LUA_DEBUG_NUM_BYTES: %d\n" % numBytes)
aBytes = ljm.eReadNameByteArray(handle, "LUA_DEBUG_DATA",
int(numBytes))
luaMessage = "".join([("%c" % val) for val in aBytes])
print("LUA_DEBUG_DATA: %s" % luaMessage)
except ljm.LJMError:
print("Error while running the main loop")
raise
def readValueI2C(self):
numBytes = 6
ljm.eWriteName(self.handle, "I2C_NUM_BYTES_TX", 0)
ljm.eWriteName(self.handle, "I2C_NUM_BYTES_RX", numBytes)
aBytes = ljm.eReadNameByteArray(self.handle, "I2C_DATA_RX", numBytes)
ljm.eWriteName(self.handle, "I2C_GO", 1)
resp = ''
for i in aBytes:
if (i > 1 and i < 255):
resp = resp + ''.join(chr(i))
if (resp == ''):
return 0
return float(resp)
def readFile(handle, sdPath):
"""Return the file contents of the specified path as a string
"""
sdPath = sanitizePath(sdPath)
path, filename = os.path.split(sdPath)
if path:
raise ValueError('cannot accept a file path that is not in the cwd')
# path = sanitizePath(path)
# goToPath(handle, path)
# This would need to be improved by adding a try/finally so that
# readFile returns to the cwd before readFile was called
dir_contents = getCurDirContents(handle)
# Get file size from the directory contents
try:
fileSize = dir_contents[filename][0]
except KeyError as excep:
raise ValueError('File not found: %s' % (sdPath))
# 1) Write the length of the file name to FILE_IO_PATH_WRITE_LEN_BYTES (add
# 1 for the null terminator);
filename_len = len(filename)
ljm.eWriteName(handle, "FILE_IO_PATH_WRITE_LEN_BYTES", filename_len)
# 2) Write the name to FILE_IO_NAME_WRITE (with null terminator)
filenameBytes = sdPath.encode()
ljm.eWriteNameByteArray(handle, "FILE_IO_PATH_WRITE", filename_len,
filenameBytes)
# 3) Write any value to FILE_IO_OPEN
ljm.eWriteName(handle, "FILE_IO_OPEN", 1)
# 4) Read file data from FILE_IO_READ (using the size from FILE_IO_SIZE)
fileDataBytes = ljm.eReadNameByteArray(handle, "FILE_IO_READ", fileSize)
# 5) Write a value of 1 to FILE_IO_CLOSE
ljm.eWriteName(handle, "FILE_IO_CLOSE", 1)
# Convert data bytes to string
fileData = "".join(chr(x) for x in fileDataBytes)
return fileData
def getCWD(handle):
"""Returns the SD card system's current working directory as a string.
"""
# 1) Write a value of 1 to FILE_IO_DIR_CURRENT. The error returned
# indicates whether there is a directory loaded as current. No error (0)
# indicates a valid directory.
ljm.eWriteName(handle, "FILE_IO_DIR_CURRENT", 1)
# 2) Read FILE_IO_PATH_READ_LEN_BYTES.
len = int(ljm.eReadName(handle, "FILE_IO_PATH_READ_LEN_BYTES"))
# 3) Read an array of size FILE_IO_PATH_READ_LEN_BYTES from
# FILE_IO_PATH_READ
nameInBytes = ljm.eReadNameByteArray(handle, "FILE_IO_PATH_READ", len)
# convert to string
nameStr = "".join(chr(x) for x in nameInBytes)
return nameStr
def getCurDirContents(handle):
"""Return the current working directory's contents as an iterable.
"""
# 1) Write a value of 1 to FILE_IO_DIR_FIRST. The error returned indicates
# whether anything was found. No error (0) indicates that something was
# found. FILE_IO_NOT_FOUND (2960) indicates that nothing was found.
ljm.eWriteName(handle, "FILE_IO_DIR_FIRST", 1)
# Loop reading name and properties of one file per iteration
more_files = True
dirContents = {}
while more_files:
# 2) Read FILE_IO_PATH_READ_LEN_BYTES, FILE_IO_ATTRIBUTES, and
# FILE_IO_SIZE_BYTES
len_file_name_as_bytes = int(
ljm.eReadName(handle, "FILE_IO_PATH_READ_LEN_BYTES"))
size = (int(ljm.eReadName(handle, "FILE_IO_SIZE_BYTES")))
attr = (int(ljm.eReadName(handle, "FILE_IO_ATTRIBUTES")))
# 3) Read an array of size FILE_IO_PATH_READ_LEN_BYTES from
# FILE_IO_PATH_READ.
file_name_as_bytes = ljm.eReadNameByteArray(handle,
"FILE_IO_PATH_READ",
len_file_name_as_bytes)
# convert to string
file_name_as_strings = "".join(chr(x) for x in file_name_as_bytes)
dirContents[file_name_as_strings] = (size, attr)
# 4) Write a value of 1 to FILE_IO_DIR_NEXT. The error returned
# indicates whether anything was found. No error (0) indicates that
# there are more items->go back to step 2. FILE_IO_INVALID_OBJECT
# (2809) and potentially error code FILE_IO_NOT_FOUND (2960)
# indicates that there are no more items->Done.
try:
ljm.eWriteName(handle, "FILE_IO_DIR_NEXT", 1)
except:
more_files = False
return dirContents
print("\nSPI Configuration:")
for i in range(numFrames):
print(" %s = %0.0f" % (aNames[i], aValues[i]))
# Write(TX)/Read(RX) 4 bytes
numBytes = 4
ljm.eWriteName(handle, "SPI_NUM_BYTES", numBytes)
# Write the bytes
dataWrite = []
dataWrite.extend([randrange(0, 256) for _ in range(numBytes)])
ljm.eWriteNameByteArray(handle, "SPI_DATA_TX", len(dataWrite), dataWrite)
ljm.eWriteName(handle, "SPI_GO", 1) # Do the SPI communications
# Display the bytes written
print("")
for i in range(numBytes):
print("dataWrite[%i] = %0.0f" % (i, dataWrite[i]))
# Read the bytes
dataRead = ljm.eReadNameByteArray(handle, "SPI_DATA_RX", numBytes)
# Display the bytes read
print("")
for i in range(numBytes):
print("dataRead[%i] = %0.0f" % (i, dataRead[i]))
# Close handle
ljm.close(handle)
1) # Set the number of bytes to transmit
ljm.eWriteName(handle, "I2C_NUM_BYTES_RX",
4) # Set the number of bytes to receive
# Set the TX bytes. We are sending 1 byte for the address.
numBytes = 1
aBytes = [0] # Byte 0: Memory pointer = 0
ljm.eWriteNameByteArray(handle, "I2C_DATA_TX", numBytes, aBytes)
ljm.eWriteName(handle, "I2C_GO", 1) # Do the I2C communications.
# Read the RX bytes.
numBytes = 4
# aBytes[0] to aBytes[3] will contain the data
aBytes = [0] * 4
aBytes = ljm.eReadNameByteArray(handle, "I2C_DATA_RX", numBytes)
print("\nRead User Memory [0-3] = %s" % " ".join([("%.0f" % val)
for val in aBytes]))
# Write EEPROM bytes 0-3 in the user memory area, using the page write
# technique. Note that page writes are limited to 16 bytes max, and must be
# aligned with the 16-byte page intervals. For instance, if you start writing
# at address 14, you can only write two bytes because byte 16 is the start of a
# new page.
ljm.eWriteName(handle, "I2C_NUM_BYTES_TX",
5) # Set the number of bytes to transmit
ljm.eWriteName(handle, "I2C_NUM_BYTES_RX",
0) # Set the number of bytes to receive
# Set the TX bytes.
def _read_array(self, register, num_bytes):
return ljm.eReadNameByteArray(self.handle, "I2C_DATA_RX", read_bytes)
def t7_startup_check(lj_handle):
"""Read various parameters from the LabJack T7 device.
Parameters that are read from the LabJack T7 include code versions, hardware serial number, etc.
The information is put into a monitor point dictionary, and the values are compared with the
requirements.
Args:
lj_handle (int): Unique handle for the LabJack driver for this antenna.
Returns:
start_up_state (dict): Dictionary of monitor points with the startup information acquired.
"""
start_up_state = dict(factory=False,
prod_id=-1,
hw_ver=0.0,
fw_ver=0.0,
boot_ver=0.0,
ser_no=0,
dev_name='',
lua_running=False,
lua_code_ver=-1,
config_valid=True)
# Read relevant device information and configuration registers.
start_up_state['factory'] = bool(
ljm.eReadName(lj_handle, 'IO_CONFIG_CHECK_FOR_FACTORY'))
start_up_state['prod_id'] = int(ljm.eReadName(lj_handle, 'PRODUCT_ID'))
start_up_state['hw_ver'] = format(
float(ljm.eReadName(lj_handle, 'HARDWARE_VERSION')), '.3f')
start_up_state['fw_ver'] = format(
float(ljm.eReadName(lj_handle, 'FIRMWARE_VERSION')), '.3f')
start_up_state['boot_ver'] = format(
float(ljm.eReadName(lj_handle, 'BOOTLOADER_VERSION')), '.3f')
start_up_state['ser_no'] = int(ljm.eReadName(lj_handle, 'SERIAL_NUMBER'))
dev_name = bytes(
ljm.eReadNameByteArray(lj_handle, 'DEVICE_NAME_DEFAULT', 49))
d_name = ''
for device in dev_name:
if device == 0:
break
d_name += chr(device)
start_up_state['dev_name'] = d_name
start_up_state['lua_running'] = bool(ljm.eReadName(lj_handle, 'LUA_RUN'))
if start_up_state['lua_running'] is False:
print('Lua script not running. Attempting to load and start script')
ljm.eWriteName(lj_handle, 'LUA_LOAD_SAVED', 1)
time.sleep(2.0)
ljm.eWriteName(lj_handle, 'LUA_RUN', 1)
time.sleep(2.0)
start_up_state['lua_running'] = bool(
ljm.eReadName(lj_handle, 'LUA_RUN'))
if start_up_state['lua_running'] is False:
print('Failed to start script')
start_up_state['config_valid'] = False
start_up_state['lua_code_ver'] = format(
float(ljm.eReadAddress(lj_handle, 46000, 3)), '.3f')
for k, val in start_up_state.items():
print(" --{}: {}".format(k, val))
if start_up_state['factory'] is False or start_up_state['prod_id'] != 7:
start_up_state['config_valid'] = False
return start_up_state
aValues = [function, numTX, numRX, romH, romL, pathH, pathL]
ljm.eWriteNames(handle, len(aNames), aNames, aValues)
ljm.eWriteNameByteArray(handle, "ONEWIRE_DATA_TX", numTX, dataTX)
ljm.eWriteName(handle, "ONEWIRE_GO", 1)
# Read the binary temperature.
print("Read the binary temperature.")
function = 0x55 # Match
numTX = 1
dataTX = [0xBE] # 0xBE = DS1822 Read scratchpad command
numRX = 2
aNames = [
"ONEWIRE_FUNCTION", "ONEWIRE_NUM_BYTES_TX", "ONEWIRE_NUM_BYTES_RX",
"ONEWIRE_ROM_MATCH_H", "ONEWIRE_ROM_MATCH_L", "ONEWIRE_PATH_H",
"ONEWIRE_PATH_L"
]
aValues = [function, numTX, numRX, romH, romL, pathH, pathL]
ljm.eWriteNames(handle, len(aNames), aNames, aValues)
ljm.eWriteNameByteArray(handle, "ONEWIRE_DATA_TX", numTX, dataTX)
ljm.eWriteName(handle, "ONEWIRE_GO", 1)
dataRX = ljm.eReadNameByteArray(handle, "ONEWIRE_DATA_RX", numRX)
temperature = (int(dataRX[0]) + (int(dataRX[1]) << 8))
if temperature == 0x0550:
print("The DS1822 power on reset value is 85 C.")
print("Read again get the real temperature.")
else:
temperature = temperature * 0.0625
print("Temperature = %f C" % temperature)
ljm.close(handle)
