The CAN communication function of the GT3U series PLC provides multiple working modes, including register sharing mode, expansion mode, CANOPEN mode, and free communication mode. The following are the key points of CAN communication:
Register sharing mode:
You can set up a host to support up to 32 slaves, and each station can share up to 32 registers.
The host and slave can read and write shared registers. The baud rate can be selected between 20K and 1000Kbps.
It should be noted that the addresses of the host and slave cannot be repeated, otherwise an error will be reported.
Extension mode:
The host can connect up to 15 expansion modules, and the function of each module is fixed (for example, module No. 1 is a digital input and output module), without any initialization program, plug and play.
In expansion mode, modules communicate through the CAN interface.
CANopen mode:
In CANOPEN mode, you need to use a PC host to set the data dictionary, or you can use From and To instructions to read and write data through the PLC program.
Support baud rates from 20K to 1000Kbps.
Free communication mode:
Use RS2 instructions to send and receive data through the CAN channel. The data format and instruction execution results can be stored and checked through specific registers.
The specific parameters and usage methods of each mode can be configured in the PLC programming software. The communication distance and maximum number of slaves of the CAN bus are related to the baud rate, and up to 32 slaves are supported.