Automatic CAN TX/RX mode
Our CAN modules support RAW CAN and J1939 within the automatic CAN TX/RX functions. Configuration is carried out conveniently using the ICT tool.
RAW CAN
RAW CAN enables CAN packets to be transmitted and received directly without a higher-level communication protocol. The following formats are supported:
- Standard CAN IDs with 11 bits
- Extended CAN IDs with 29 bits
The CAN ID is entered directly in the ICT tool. In addition, it is specified which I/O data is to be transmitted or how received data is to be processed.
RAW CAN is particularly suitable for proprietary CAN protocols, predefined message structures and direct communication between CAN nodes.
J1939
SAE J1939 is a CAN-based communication protocol used in commercial vehicles, agricultural and construction machinery, as well as industrial applications.
J1939 uses a 29-bit CAN ID that contains information about the priority, message content, sender and, if applicable, recipient.
The main components are:
Prio – Priority
Defines the priority of the message. The value range is between 0 and 7, with a lower value indicating a higher priority.
PGN – Parameter Group Number
Identifies the content and function of the message.
SA – Source Address
Specifies the address of the transmitting CAN node.
DA – Destination Address
Specifies the address of the recipient for destination-specific messages.
TX Mode
Auto TX mode enables CAN packets to be transmitted automatically to other bus nodes. The module’s digital and analog input signals can be transmitted either cyclically at defined intervals or depending on specified input states.
Alternatively, a trigger event can be defined. In this case, a CAN packet is only transmitted after a specific packet has been received on a defined CAN ID, for example a CAN sync message on ID 0x80.
The following settings can be configured:
- Enable or disable TX mode
- CAN Mode: RAW CAN with an 11-bit or 29-bit CAN ID, or J1939
- Destination address or CAN ID
- TX Mode
- Trigger Mode
- Transmission interval
RX Mode
Auto RX mode enables the automatic processing of received CAN packets. The data contained in the packets is forwarded directly to the module’s analog or digital outputs. This allows relay outputs to be controlled by another node on the CAN bus, for example.
The following settings can be configured:
- Enable or disable RX mode
- CAN Mode: RAW CAN with an 11-bit or 29-bit CAN ID, or J1939
- CAN ID to be received or source address
- RX Mode
