def adc_read(port, pin, raw=False):
"""
Reads a raw or converted ADC value.
Args:
port: The port of the GPIO pin to read from.
pin: The pin number of the GPIO pin to read from.
raw: If raw is True, a raw read should be performed; otherwise a converted read.
Defaults to converted.
Returns:
The ADC reading as a 16-bit integer.
Raises:
ValueError: if the range of the input args is invalid.
Exception: if we receive a nonzero status code.
"""
# If port is entered as a str, convert to int
if isinstance(port, str):
port = getattr(GpioPort, port.capitalize())
# Check the ranges of input args
if port < 0 or port >= GpioPort.NUM_GPIO_PORTS:
raise ValueError("ERROR: invalid GPIO port")
if pin < 0 or pin >= NUM_PINS_PER_PORT:
raise ValueError("ERROR: invalid GPIO pin number")
if raw not in (True, False):
raise ValueError("ERROR: raw must be a bool value")
# Send CAN message
data = [
(port, 1),
(pin, 1),
(raw, 1),
]
data = can_util.can_pack(data)
can_util.send_message(babydriver_id=BabydriverMessageId.ADC_READ_COMMAND, data=data)
# Wait to receive the first CAN message with data
data_msg = can_util.next_message(babydriver_id=BabydriverMessageId.ADC_READ_DATA)
# Extract the low and high bytes of the ADC conversion
result_low = data_msg.data[1]
result_high = data_msg.data[2]
# Wait to receive the second CAN message with status
status_msg = can_util.next_message(babydriver_id=BabydriverMessageId.STATUS)
status = status_msg.data[1]
# Check if status is not ok
if status != OK_STATUS:
raise Exception("ERROR: received a nonzero STATUS_CODE: {}".format(status))
return (result_high << 8) | result_low
def i2c_read(port, address, rx_len, reg=None):
"""
Reads a number of bytes over I2C
Args:
port: I2C port (1 or 2) to read from
address: I2C address to read from
rx_len: expected response length
reg: register to read from, or None if it is a normal read (non-register read)
Raises:
ValueError: if parameters passed into i2c_read are invalid
Exception: if a non-zero status code was received
"""
is_reg = 0
if reg is None:
reg = 0
else:
is_reg = 1
if port not in (1, 2):
raise ValueError("Expected port of 1 or 2 ")
if address < 0 or address > 255:
raise ValueError("Expected an uint8 address between 0 and 255")
if rx_len < 0 or rx_len > 255:
raise ValueError(
"Expected an uint8 response length value between 0 and 255")
if reg < 0 or reg > 255:
raise ValueError("Expected an uint8 register between 0 and 255")
# shift port to 0 or 1, and send can message
data_pack = can_util.can_pack([(port - 1, 1), (address, 1), (rx_len, 1),
(is_reg, 1), (reg, 1)])
can_util.send_message(babydriver_id=BabydriverMessageId.I2C_READ_COMMAND,
data=data_pack)
read_data = []
num_msgs = ceil(rx_len / 7)
# Loop to receive the ceil(rx_len/7) CAN messages, with only the
# last 7 bytes of each msg being data and storing only rx_len bytes
# of data to the read_data list
for message in range(num_msgs):
read_msg = can_util.next_message(
babydriver_id=BabydriverMessageId.I2C_READ_DATA)
if message == (num_msgs - 1) and (rx_len % 7) != 0:
read_data.extend(read_msg.data[1:rx_len % 7 + 1])
else:
read_data.extend(read_msg.data[1:8])
# Wait to receive the status CAN message
status_msg = can_util.next_message(
babydriver_id=BabydriverMessageId.STATUS)
status = status_msg.data[1]
# Check if status is not STATUS_CODE_OK (0)
if status != 0:
raise Exception("Received STATUS_CODE {}".format(status))
return read_data
def can_send_raw(msg_id, data, device_id=BABYDRIVER_DEVICE_ID, channel=None):
"""
A wrapper over can_utils.send_message providing a friendlier interface to can_util.send_message.
Args:
msg_id: CAN message ID
(if it's for babydriver messages, then msg_id=BABYDRIVER_CAN_MESSAGE_ID)
data: a list of up to 8 bytes of data to send
device_id: the device ID to send from
channel: CAN channel
"""
can_util.send_message(
data=data,
channel=channel,
msg_id=msg_id,
device_id=device_id,
)
def i2c_write(port, address, tx_bytes, reg=None):
"""
Writes over I2C to the given port/address
Args:
port: port of the I2C to write to (1 or 2)
address: I2C address to write to (0-255)
tx_bytes: list of bytes to write over I2C (a list of ints 0-255)
reg: the register to write to, or None if no register is required
Raises:
Exception: if a non-zero status code was received
"""
if port not in (1, 2):
raise ValueError("Expected port of 1 (I2C_PORT_1) or 2 (I2C_PORT_2)")
if address < 0 or address > 255:
raise ValueError("Expected address between 0 and 255")
if not all(0 <= byte < 256 for byte in tx_bytes):
raise ValueError("Expected list of bytes between 0 and 255")
is_reg = 0
if reg is None:
reg = 0
else:
is_reg = 1
if reg < 0 or reg > 255:
raise ValueError("Expected register to write to between 0 and 255")
can_pack = can_util.can_pack([(port - 1, 1), (address, 1),
(len(tx_bytes), 1), (is_reg, 1), (reg, 1)])
can_util.send_message(
babydriver_id=BabydriverMessageId.I2C_WRITE_COMMAND,
data=can_pack,
)
# Sends CAN message
for i in range(0, len(tx_bytes), 7):
can_util.send_message(
babydriver_id=BabydriverMessageId.I2C_WRITE_DATA,
data=tx_bytes[i:i + 7],
)
status_msg = can_util.next_message(
babydriver_id=BabydriverMessageId.STATUS)
# Raises Exception if status is non-OK
if status_msg.data[1] != 0:
raise Exception("Received STATUS_CODE {}".format(status_msg.data[1]))
def unregister_gpio_interrupt(port, pin):
"""
Unregisters a gpio interrupt on a pin
Args:
port: Port of the GPIO pin to register an interrupt in
pin: Pin number of the GPIO pin to register an interrupt in
Raises:
Value error: if the parameters passed into register_gpio_interrupt are incorrect
Attribute error: if the port parameter is invalid (refer gpio_port.py
for acceptable port parameters)
Exception: if a non-zero status code is received when attempting to uregister an interrupt
Key error: if no interrupt is registered in the given port and pin
"""
if isinstance(port, str):
port = getattr(GpioPort, port.capitalize())
if port < 0 or port >= GpioPort.NUM_GPIO_PORTS:
raise ValueError("invalid GPIO port (Range: 'A' - 'F')")
if pin < 0 or pin >= NUM_PINS_PER_PORT:
raise ValueError("Invalid GPIO pin number (Range: 0 - 15)")
msg_data_unregister_gpio_interrupt = [(port, 1), (pin, 1)]
can_util.send_message(
babydriver_id=message_defs.BabydriverMessageId.GPIO_IT_UNREGISTER_COMMAND,
data=can_util.can_pack(msg_data_unregister_gpio_interrupt)
)
status_message = can_util.next_message(babydriver_id=message_defs.BabydriverMessageId.STATUS)
received_status = status_message.data[1]
# Check if status is invalid (0 refers to STATUS_CODE_OK)
if received_status != 0:
raise Exception("Received a nonzero STATUS_CODE: {}".format(received_status))
# Clearing callback related to the interrupt that was unregistered
if (port, pin) not in callback_dict:
raise KeyError("No interrupt registered on given port and pin")
del callback_dict[(port, pin)]
def gpio_get(port, pin):
'''
Returns the state of the GPIO pin at the given port and pin number as a bool
The port can be entered as either a string or int value (e.g. 'A' or 0).
The pin is an int value
'''
if isinstance(port, str):
port = getattr(GpioPort, port.capitalize())
if port < 0 or port >= GpioPort.NUM_GPIO_PORTS:
raise ValueError("ERROR: invalid GPIO port")
if pin < 0 or pin >= GPIO_PINS_PER_PORT:
raise ValueError("ERROR: invalid GPIO pin number")
data = can_util.can_pack([(port, 1), (pin, 1)])
can_util.send_message(
babydriver_id=BabydriverMessageId.GPIO_GET_COMMAND,
data=data,
)
gpio_data_msg = can_util.next_message(
babydriver_id=BabydriverMessageId.GPIO_GET_DATA,
)
status_msg = can_util.next_message(
babydriver_id=BabydriverMessageId.STATUS,
)
status = status_msg.data[1]
if status != 0:
raise Exception("ERROR: Non-OK status returned: {}".format(status))
raw_state = gpio_data_msg.data[1]
gpio_pin_state = bool(raw_state)
return gpio_pin_state
def gpio_set(port, pin, state):
"""
Sets a GPIO pin
Args:
port: port of the GPIO pin to set (can be entered as either a string or integer)
pin: pin number of the GPIO pin to set
state: 0 if setting low, 1 if setting high
Raises:
AttributeError: if port parameter is entered as a string and is invalid
ValueError: if parameters passed into gpio_set are invalid
Exception: if a non-zero status code was received
"""
# If given port as a string, it is converted to a string
if isinstance(port, str):
port = getattr(GpioPort, port.capitalize())
# Checks whether valid parameters were passed into gpio_set
if port < 0 or port >= GpioPort.NUM_GPIO_PORTS:
raise ValueError("Expected port between A and {}".format(
chr(GpioPort.NUM_GPIO_PORTS + ord('A') - 1)
))
if pin < 0 or pin >= NUM_PINS_PER_PORT:
raise ValueError("Expected pin between 0 and {}".format(NUM_PINS_PER_PORT - 1))
if state not in (0, 1):
raise ValueError("Expected state of 0 (low) or 1 (high)")
can_pack_args = [(port, 1), (pin, 1), (state, 1)]
can_util.send_message(
babydriver_id=BabydriverMessageId.GPIO_SET,
data=can_util.can_pack(can_pack_args)
)
gpio_set_status = can_util.next_message(babydriver_id=BabydriverMessageId.STATUS)
# Checks for valid status code
if gpio_set_status.data[1] != 0:
raise Exception("Received STATUS_CODE {}".format(gpio_set_status.data[1]))
def register_gpio_interrupt(port, pin, edge=InterruptEdge.RISING_AND_FALLING, callback=None):
"""
Registers a gpio interrupt on a pin
Args:
port: port of the GPIO pin to register an interrupt in
pin: pin number of the GPIO pin to register an interrupt in
edge: callback function is called when this interrupt edge occurs. Can be entered as a
string or a number (RISING (0), FALLING (1) or RISING_AND_FALLING (2))
callback: if callback is None, a default callback function will be called
that prints "Interrupt on P<port><pin>: <edge>" in this format.
The user-defined callback function should follow this format:
function_name(info) where the only parameter is info,
a named tuple which holds the port (info.port),pin (info.pin) and
edge (info.edge) of the GPIO interrupt that occured.
Raises:
Value error: if the parameters passed into register_gpio_interrupt are incorrect
Attribute error: if the port parameter or interrupt edge is invalid (refer gpio_port.py
for acceptable port parameters and InterruptEdge for appropriate edge
parameters)
Exception: if a non-zero status code is received when attempting to register an interrupt
Type error: if the callback function (called when interrupt occurs) is of incorrect format
Note: There is a hard STM32 limit that only one GPIO interrupt can be registered at a time
per pin number. For example, PA2 and PB2 would share the same GPIO pin.
"""
if isinstance(port, str):
port = getattr(GpioPort, port.capitalize())
if port < 0 or port >= GpioPort.NUM_GPIO_PORTS:
raise ValueError("invalid GPIO port (Range: 'A' - 'F')")
if pin < 0 or pin >= NUM_PINS_PER_PORT:
raise ValueError("Invalid GPIO pin number (Range: 0 - 15)")
if isinstance(edge, str):
if edge.upper() not in InterruptEdge.__members__:
raise AttributeError("Enter 'RISING', 'FALLING' or 'RISING_AND_FALLING' for "
"interrupt edge")
edge = InterruptEdge[edge.upper()]
if edge < 0 or edge >= InterruptEdge.NUM_INTERRUPT_EDGES:
raise ValueError("invalid interrupt edge (enter 0 (Rising), 1 (Falling) "
"or 2 (Rising_and_falling")
if callback is not None and not callable(callback):
raise ValueError("invalid callback function")
msg_data_register_gpio_interrupt = [(port, 1), (pin, 1), (edge, 1)]
can_util.send_message(
babydriver_id=message_defs.BabydriverMessageId.GPIO_IT_REGISTER_COMMAND,
data=can_util.can_pack(msg_data_register_gpio_interrupt)
)
status_message = can_util.next_message(babydriver_id=message_defs.BabydriverMessageId.STATUS)
received_status = status_message.data[1]
# Check if status is invalid (0 refers to STATUS_CODE_OK)
if received_status != 0:
raise Exception("received a nonzero STATUS_CODE: {}".format(received_status))
# Adding callback to dictionary to be called upon when interrupt occurs
if callback is None:
callback_dict[(port, pin)] = default_callback
else:
callback_dict[(port, pin)] = callback
def spi_exchange(tx_bytes,
rx_len,
spi_port=1,
spi_mode=0,
baudrate=6000000,
cs=None):
"""
Sends data through SPI
The tx_bytes is an int array
The rx_len is a non-negative int.
The spi_port is a non-negative int.
The spi_mode is a non-negative int.
The baudrate is a non-negative int.
The CS pin, if not None, is a tuple (port, pin), where pin is an
int in [0, NUM_PINS_PER_PORT) and port is either an int in [0, NUM_GPIO_PORTS),
or a string 'a' through 'f', case insensitive
Args:
tx_bytes: The bytes to TX.
rx_len: Number of bytes to RX
spi_port: port of the pin to perform SPI exchange on (1 or 2)
spi_mode: SPI mode to use (0, 1, 2 or 3)
baudrate: baudrate to use (defaults to 6000000)
cs: chip select port and pin to use (defaults to (1, 1))
Raises:
AttributeError: if cs_port parameter is entered as a string and is invalid
ValueError: if spi_port, spi_mode, rx_len, cs_port, cs_pin don't meet their requirements
Exception: if a non-zero status code was received.
"""
if spi_port not in (1, 2):
raise ValueError("ERROR: Expected SPI port 1 or 2")
if spi_mode not in (0, 1, 2, 3):
raise ValueError("ERROR: Expected mode between 0 and 3")
# pylint: disable=superfluous-parens
if not (0 <= len(tx_bytes) <= 255):
raise ValueError(
"ERROR: numbers of tx_bytes must be between 0 and 255")
# pylint: disable=superfluous-parens
if not (0 <= rx_len <= 255):
raise ValueError(
"ERROR: rx_len must be a non-negative integer between 0 and 255")
if baudrate < 0:
raise ValueError("ERROR: baudrate must be a non-negative integer")
cs_port = 0 if cs is None else cs[0]
cs_pin = 0 if cs is None else cs[1]
use_cs = 0 if cs is None else 1
if isinstance(cs_port, str):
cs_port = getattr(GpioPort, cs_port.capitalize())
if cs_port < 0 or cs_port >= GpioPort.NUM_GPIO_PORTS:
raise ValueError("ERROR: Expected CS port between A and {}".format(
chr(GpioPort.NUM_GPIO_PORTS + ord('A') - 1)))
if cs_pin < 0 or cs_pin >= GPIO_PINS_PER_PORT:
raise ValueError("ERROR: Expected CS pin between 0 and {}".format(
GPIO_PINS_PER_PORT - 1))
data1 = [
(spi_port - 1, 1), # 0 for SPI_PORT 1, 1 for SPI_PORT_2
(spi_mode, 1),
(len(tx_bytes), 1), # tx_len
(rx_len, 1),
(cs_port, 1),
(cs_pin, 1),
(use_cs, 1),
]
data2 = [(baudrate, 4)]
can_util.send_message(
babydriver_id=BabydriverMessageId.SPI_EXCHANGE_METADATA_1,
data=can_util.can_pack(data1))
can_util.send_message(
babydriver_id=BabydriverMessageId.SPI_EXCHANGE_METADATA_2,
data=can_util.can_pack(data2))
# collect bytes into groups of 7
chunks = [tx_bytes[x:x + 7] for x in range(0, len(tx_bytes), 7)]
for data in chunks:
# pad with 0s if length isn't 7
if len(data) < 7:
data += [0] * (7 - len(data))
tmp = [(d, 1) for d in data]
can_util.send_message(
babydriver_id=BabydriverMessageId.SPI_EXCHANGE_TX_DATA,
data=can_util.can_pack(tmp))
# Receive bytes
rx_bytes_left = rx_len
rx_data = []
while rx_bytes_left > 0:
rx_msg = can_util.next_message(
babydriver_id=BabydriverMessageId.SPI_EXCHANGE_RX_DATA)
msg_data = rx_msg.data
# list constructor to handle bytearrays
rx_data += list(msg_data[1:min(rx_bytes_left + 1, 8)])
rx_bytes_left -= 7
status = can_util.next_message(babydriver_id=BabydriverMessageId.STATUS)
if status.data[1] != 0:
raise Exception("ERROR: Received non-zero status code: {}".format(
status.data[1]))
return rx_data