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ae51a22fbb
RIOT implementation of CAN bus relies on SocketCAN model.
Since commit c398e56 (can: add optional DLC element to Classical CAN
frame structure), '__u8 can_dlc' attribute of struct can_frame is
considered as deprecated in SocketCAN and kept for legacy support.
Attribute '__u8 len' should be used instead.
union {
/* CAN frame payload length in byte (0 .. CAN_MAX_DLEN)
* was previously named can_dlc so we need to carry that
* name for legacy support
*/
__u8 len;
__u8 can_dlc; /* deprecated */
};
Moreover, CAN FD frame structure does not support legacy attribute
'can_dlc', making 'len' mandatory for incoming CAN FD support in RIOT.
struct canfd_frame {
canid_t can_id; /* 32 bit CAN_ID + EFF/RTR/ERR flags */
__u8 len; /* frame payload length in byte */
__u8 flags; /* additional flags for CAN FD */
__u8 __res0; /* reserved / padding */
__u8 __res1; /* reserved / padding */
__u8 data[CANFD_MAX_DLEN]
__attribute__((aligned(8)));
};
Signed-off-by: Gilles DOFFE <gilles.doffe@rtone.fr>
candev test application
About
This application is a test for using the candev abstraction directly. Use this if you want to use a single CAN driver and thus don't need the CAN-DLL layer.
The CAN_DRIVER variable is used to select the default CAN_DRIVER, supported alternatives are:
- MCP2515 to use
mcp2515stand-alone CAN controller - PERIPH_CAN to use
periph_cancontroller, usually requires a CAN transceiver as well: e.g.tja1042orncv7356(except for native)
Usage
Sending
Messages can be sent over the CAN-bus through the send command. Optionally, up to 8 bytes can be passed as arguments (in decimal form). If no arguments are passed it will default to sending AB CD EF (hex).
> send <bytes>
# e.g.: send AA BB CC
> send 170 187 204
send 170 187 204
Receiving
The test-app is always listening for incoming CAN messages. They will be stored asynchronously in a buffer and can be requested by means of the receive command. Optionally, an argument n can be passed to receive n messages in a row.
> receive <n>
# e.g.:
> receive 2
Reading from Rxbuf...
id: 1 dlc: 3 Data:
0xAA 0xBB 0xCC
Reading from Rxbuf...
id: 1 dlc: 3 Data:
0xAA 0xBB 0xCC
Native Setup
Refer to README.native.can.md.