1 Overview

GCAN-204 converter has one CAN-Bus interface, one serial interface. The GCAN-204 integrates the Modbus RTU protocol. With the GCAN-204 , user can use the serial bus connect to other equipment (with Modbus RTU protocol)  access the CAN-Bus communication interface.
GCAN-204 has integrated isolation protection module. Using DIN railway fixed, it can be easier to integrate into the control cabinet.

2 Properties at a glance

Modbus slave support function code: 03H, 04H, 06H, 16H
 Serial baud rate: 600bps ~ 115200bps
 CAN-Bus supports CAN2.0A and CAN2.0B frame format, conform to ISO/DIS 11898 standards
 CAN baud rates: 5Kbps ~ 1Mbps
 CAN-Bus isolation module insulation voltage: DC 1500V
 Power supply: 9~30V (20mA，24V DC)
 Interface using terminal blocks
 Installation method: DIN rail
 Working temperature range from -40 to 85 °C
 Size: (L)113mm * (W)100mm * (H)21mm

3. Examples

The user can use the included serial debugging assistant to send Modbus instruction debugging.
Please note: choose "hexadecimal display" and "hexadecimal send" when using the serial debugging assistant.

3.1 Receive CAN data

For example, configure the Modbus slave address: 1, Modbus register first address: 0x01, CAN: standard frame, frame ID: 0x181, CAN frame data: 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08.
User Modbus master sends request frame:
01 03 00 01 00 04 15 C9
GCAN-204 response frame:
01 03 08 02 01 04 03 06 05 08 07 17 C1
Please note that the CRC is calculated by the CRC16 checksum calculator. (With disk)
At this point, the GCAN-204 module has received a data frame with a frame ID of 0x181 from the CAN terminal of other equipment.

3.2 Transmit CAN data

For example, Modbus slave address: 1, Modbus register first address: 0x101 (decimal: 257), function code: 16 (10H), CAN: standard frame, frame ID: 0x201, CAN frame data: 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08.
User Modbus master sends request frame:
01 10 01 01 00 04 08 02 01 04 03 06 05 08 07 CB 2E
GCAN-204 response frame:
01 10 01 01 00 04 91 F6
Please note that the CRC is calculated by the CRC16 checksum calculator.
At this point, the CAN terminal of other equipment has received a data frame with a frame ID of 0x201 from the Modbus side of the GCAN-204 module.