CAN_recv block

Short summary

Name	`CAN_recv`
→POU type	→function
Category	system blocks from "logi.library", Blocks for CAN , block with internal error diagnostic
Graphical interface
Available since	version 1.85.0 (for Neuron Power Engineer) and version 3.4.0 of Neuron RTS max – initial variant version 1.111.0 (for Neuron Power Engineer) and version 3.19.0 of Neuron RTS max – enhancement: new inputs `HANDLE` and `DATA`, changed name for output `CANID` (instead of name `ID`), no output `DATA` any longer, additional return codes for output `RC` This block is supported for →phyBOARD-Regor, →phyBOARD-Wega and →µMIC.200.

Functionality

The block receives CANopen or CAN 2.0 messages.

Inputs, outputs

	Identifier	→Data type	Description
Inputs:	`HANDLE`	`DINT`	handle of the CAN interface (with initial value `-1`)
Inputs:	`DATA`	`REF_TO ARRAY[0..7] of BYTE`	→reference to the transmission data
Outputs:	`CANID`	`UDINT`	CAN 2.0 or CANopen message ID
	`DLC`	`USINT`	number of the received data bytes in the CAN message (= data length code)
	`RC`	`CAN_RETURN_CODE`	return code of the block call as specified in data type `CAN_RETURN_CODE` with the following values: `CAN_OK`, `CAN_RECEIVE_ERROR`, `CAN_NO_RECEIVE_DATA_REFERENCE`, `CAN_SYSTEM_SERVICE_NOT_LOADED`, `CAN_NO_VALID_HANDLE`, `CAN_NO_CONNECTION`, `CAN_INTERFACE_SLOT_UNUSED`

Input EN and output ENO are available when →calling the block. See "Execution control: EN, ENO" for information on input EN and output ENO.

See:

"Blocks for safe logic" whether this block is supported for developing safety-relevant applications.
"Highlighting safe logic in the FBD-editor" for the effects when using the block as a block for safe logic.

Internal error diagnostic for block

The block checks the following error cases and – if they occur – the block sets the output ENO of the block value FALSE (or an equivalent): The return code of the block has not been 0 (see the above table under RC).

Example for usage within ST-editor

Best practice in order to get to know the usage of the CAN blocks: Create a new project based on the project template Simple Neuron Power Engineer CANopen Project for PHYTEC phyBOARD-Regor and study this sample project. This project contains a usage of this block.