I am trying to receive something on OpenMV H7 via CAN-bus. I am using the example for CAN on the IDE, and if configured as transmitter, I can successfully transmit messages and see them on the bus using a CAN-Analyzer tool. However, when I send messages from the tool, or any other device, I can't seem to make it receive anything if they are extended messages. If I initialize CAN with extframe=False, and I transmit standard ID messages, I can receive them. But if I use extframe=True, and I transmit extended ID messages, I can't receive anything. Does anyone know if there is something else missing to make it work with receiving extended ID CAN messages?
This is the code I'm using currently:
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# CAN Shield Example # # This example demonstrates CAN communications between two cameras. # NOTE: you need two CAN transceiver shields and DB9 cable to run this example. import time, omv from pyb import CAN from pyb import LED RED_LED_PIN = 1 # NOTE: Set to False on receiving node. TRANSMITTER = False #TRANSMITTER = True can = CAN(2)#, CAN.NORMAL) # Set a different baudrate (default is 250Kbps) # NOTE: The following parameters are for the H7 only. # # can.init(CAN.NORMAL, prescaler=32, sjw=1, bs1=8, bs2=3) # 125Kbps #can.init(CAN.NORMAL,extframe=True, prescaler=16, sjw=1, bs1=8, bs2=3,auto_restart=True) # 250Kbps can.init(CAN.NORMAL,extframe=True, prescaler=16, sjw=1, bs1=8, bs2=3,auto_restart=True) # 250Kbps # can.init(CAN.NORMAL, prescaler=8, sjw=1, bs1=8, bs2=3) # 500Kbps # can.init(CAN.NORMAL, prescaler=4, sjw=1, bs1=8, bs2=3) # 1000Kbps #can.restart() LED(RED_LED_PIN).off() if (TRANSMITTER): while (True): # Send message with id 1 can.send('Hello', 2) time.sleep(1000) else: # Runs on the receiving node. if (omv.board_type() == 'H7'): # FDCAN # Set a filter to receive messages with id=1 -> 4 # Filter index, mode (RANGE, DUAL or MASK), FIFO (0 or 1), params can.setfilter(0,CAN.MASK,0,(0,0)) #can.setfilter(1,CAN.MASK,1,(0,0)) LED(RED_LED_PIN).on() #can.setfilter(0, CAN.RANGE, 0, (1, 4)) else: # Set a filter to receive messages with id=1, 2, 3 and 4 # Filter index, mode (LIST16, etc..), FIFO (0 or 1), params can.setfilter(0, CAN.LIST16, 0, (1, 2, 3, 4)) while (True): # Receive messages on FIFO 0 if (can.any(0)): print(can.recv(0,timeout=20)) #else: # print(can.info()) # time.sleep(100) # print(can.recv(0, timeout=100)) # except: # print("no receive\n")