Mikroelektronika MIKROE-442 데이터 시트
mikroBasic PRO for dsPIC30/33 and PIC24
MikroElektronika
255
CANxWrite
Prototype
sub function CANxWrite(dim id as longint, dim byref data_ as byte[1], dim
dataLen, CAN_TX_MSG_FLAGS as word) as word
Description If at least one empty Transmit Buffer is found, the function sends message in the queue for
transmission.
Parameters -
id
: CAN message identifier. Valid values: 11 or 29 bit values, depending on message type (standard
or extended)
-
data
: data to be sent
-
dataLen
: data length. Valid values:
0..8
-
CAN_RX_MSG_FLAGS
: message flags. Valid values:
CAN_TX_MSG_FLAGS
constants. See CAN_TX_
MSG_FLAGS constants.
Returns
-
0
if all Transmit Buffers are busy
-
0xFFFF
if at least one Transmit Buffer is available
Requires
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.
Example
‘ send message extended CAN message with appropriate ID and data
dim tx_flags as word
data as byte[8]
msg_id as longint
...
CAN1SetOperationMode(_CAN_MODE_NORMAL,0xFF) ‘ set NORMAL mode (CAN1 must
be in mode in which transmission is possible)
tx_flags = _CAN_TX_PRIORITY_0 and
_CAN_TX_XTD_FRAME and
_CAN_TX_NO_RTR_FRAME ‘ set message flags
CAN1Write(msg_id, data, 1, tx_flags)
Notes
- 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.