Mikroelektronika MIKROE-442 Datenbogen

254

mikoBasic PRO for dsPIC30/33 and PIC24

MikroElektronika

CANxRead

sub function CANxRead(dim byref id as longint, dim byref data as byte[1], 

dim dataLen, CAN_RX_MSG_FLAGS as word) as word

Description If at least one full Receive Buffer is found, it will be processed in the following way:

- Message ID is retrieved and stored to location pointed by

 id

 pointer 

- Message data is retrieved and stored to array pointed by 

data

 pointer 

- Message length is retrieved and stored to location pointed by 

dataLen

 pointer 

- Message flags are retrieved and stored to location pointed by 

CAN_RX_MSG_FLAGS

 pointer 

Parameters - 

id

: message identifier address 

- 

data

: an array of bytes up to 8 bytes in length 

- 

dataLen

: data length address 

- 

CAN_RX_MSG_FLAGS

: message flags address. For message receive flags format refer to 

CAN_RX_

MSG_FLAGS 

constants. See CAN_RX_MSG_FLAGS constants.

- 

0

 if nothing is received 

- 

0xFFFF

 if one of the Receive Buffers is full (message received) 

MCU with the CAN module.

MCU must be connected to the CAN transceiver (MCP2551 or similar) which is connected to the CAN 

bus.

CAN must be in Config mode, otherwise the function will be ignored. See CANxSetOperationMode.

dim msg_rcvd, rx_flags, data_len as word

    data as byte[8]

    msg_id as longint

CAN1SetOperationMode(_CAN_MODE_NORMAL,0xFF)   ‘ set NORMAL mode (CAN1 module 

...

rx_flags = 0                                 ‘ clear message flags

if (msg_rcvd = CAN1Read(msg_id, data, data_len, rx_flags)<>0) then

  ...

- CAN library routine require you to specify the module you want to use. To use the desired CAN 

module, simply change the letter 

x in the routine prototype for a number from 1 to 2. 

- Number of CAN modules per MCU differs from chip to chip. Please, read the appropriate datasheet 

before utilizing this library.