def get_joystick(ser):
cmd = [0, 2]
cmd.extend([0, 0, 0, 0, 0, 0, 0, 0])
comms.send_cmd(ser, cmd)
returnvalue = ser.read(2)
if returnvalue != b'':
return list(returnvalue)
def echo(ser, number_list):
cmd = [0, 1]
cmd.extend(number_list)
comms.send_cmd(ser, cmd)
returnvalue = ser.read(8)
if returnvalue != b'':
return list(returnvalue)
def mcp2515_read(ser, address, data_length):
cmd = [2, 3, address, data_length, 0, 0, 0, 0, 0, 0]
comms.send_cmd(ser, cmd)
returncode = ser.read(data_length)
if returncode != b'':
return int.from_bytes(returncode, byteorder='big')
return -1
def mcp2515_read_status(ser):
cmd = [2, 0, 0, 0, 0, 0, 0, 0, 0, 0]
comms.send_cmd(ser, cmd)
read_status = ser.read(1)
if read_status != b'':
return int.from_bytes(read_status, byteorder='big')
return None
def can_pending_rx_buffer(ser):
cmd = [3, 3]
cmd.extend([0, 0, 0, 0, 0, 0, 0, 0])
comms.send_cmd(ser, cmd)
returncode = ser.read(2)
print(returncode, list(returncode))
if returncode != b'':
return list(returncode)
return None
def motor_read_encoder(ser):
cmd = [4, 1]
cmd.extend([0,0,0,0,0,0,0,0])
comms.send_cmd(ser, cmd)
returncode = ser.read(2)
if returncode != b'':
return int.from_bytes(returncode, byteorder='big', signed=True)
def write_can_rx_flag(ser, value):
""" This is a helper function to set the receive_can_on_interrupt_flag """
cmd = [2, 8, value, 0, 0, 0, 0, 0, 0, 0]
comms.send_cmd(ser, cmd)
status = ser.read(1)
if status != b'':
status = int.from_bytes(status, byteorder='big')
if status == 0:
return 0
raise Exception
def mcp2515_init(ser, mode):
if not isinstance(mode, MCP_MODE):
raise TypeError('mode is not a valid MPC_MODE')
cmd = [2, 1, mode, 0, 0, 0, 0, 0, 0, 0]
comms.send_cmd(ser, cmd)
returncode = ser.read(1)
if returncode != b'':
return int.from_bytes(returncode, byteorder='big')
return -1
def sram_read(ser, address):
cmd = [1, 1]
cmd.extend(list(address.to_bytes(2, byteorder='big')))
cmd.extend([0,0,0,0,0,0])
comms.send_cmd(ser, cmd)
returncode = ser.read(1)
if returncode != b'':
return int.from_bytes(returncode, byteorder='big')
return -1
def can_valid_tx_buffer(ser):
cmd = [3, 2]
cmd.extend([0, 0, 0, 0, 0, 0, 0, 0])
comms.send_cmd(ser, cmd)
returncode = ser.read(2)
print(returncode)
if returncode != b'':
return list(returncode)
return None
def can_transmit(ser, msg_id, msg_len, msg_data):
cmd = [3, 0]
cmd.extend(list(msg_id.to_bytes(2, byteorder='big')))
cmd.append(msg_len)
cmd.extend(msg_data)
cmd_empty_len = 10 - (msg_len + 5)
empty_vector = [0] * (cmd_empty_len)
cmd.extend(empty_vector)
comms.send_cmd(ser, cmd)
returncode = ser.read(1)
if returncode != b'':
return int.from_bytes(returncode, byteorder='big')
return -1
def synchronize(ser):
""" Tries to sync sender and receiver.
Returns 0 on success
Returns 1 on failiure
"""
_timeout = ser.timeout
ser.timeout = 0.1
cmd = [0]
for i in range(0, 100):
comms.send_cmd(ser, cmd)
returnvalue = ser.read(1)
if returnvalue != b'':
if int.from_bytes(returnvalue, byteorder='big') == 1:
ser.timeout = _timeout
return 0
ser.timeout = _timeout
return 1
def can_receive(ser):
cmd = [3, 1]
cmd.extend([0, 0, 0, 0, 0, 0, 0, 0])
comms.send_cmd(ser, cmd)
# Check the can_status.
# The first byte returned will be the can_status. A 0 indicated that
# we received a message, a 1 indicates that we did not
returncode = ser.read(1)
#print("Returncode:", returncode)
if returncode != b'':
# Not a zero indicates no message received. Return 1 to indicate failiure
if int.from_bytes(returncode, byteorder='big') != 0:
# print("No message received")
return 1
raw_data = ser.read(11)
#print("Raw_data:", raw_data, list(raw_data))
if raw_data != b'':
# Convert the data into a nicer format
# The main thing is to combine two bytes into the ID,
# and throw away data bytes that are not actually valid. (We will always
# get 11 bytes, but not all are valid data because the data.len matters)
ID = int.from_bytes(raw_data[0:2], byteorder='big')
Length = int.from_bytes(raw_data[2:3], byteorder='big')
data = list(raw_data[3:4 + Length - 1])
print("Received a message width ID={}, len={}, data={}".format(
ID, Length, data))
returnlist = [ID, Length]
returnlist.extend(data)
return returnlist
return 1
