ECAN-240-FD (Modbus TCP to 2-port CAN FD Gateway) User Manual
Version 1.0.0
Page
:
43
Copyright © 2022 ICP DAS Co., Ltd. All Rights Reserved E-mail: service@icpdas.com
5. Modbus Information
The ECAN-240-FD module supports two Modbus function codes (0x04 and 0x10), as described
in the table below.
Code
Function
Description
04 (0x04)
Read the Input
Registers
This function code is used to read either the input registers of
received CAN/CAN FD messages or the current CAN bus
status in input data area.
16 (0x10)
Presset Multiple
Registers
This function code is used to set multiple output registers that
are used to store one or many CAN/CAN FD messages that
want to be transmitted out in output data area
5.1 Modbus/CAN Mapping Table
Users can access the CAN//CAN FD messages by using these Modbus address defined by
ECAN-240-FD module. These Modbus address can be divided into two parts as below.
Input Data Area (access by Modbus Function Code 0x04)
Output Data Area (access by Modbus Function Code 0x10)
Input/Output Data to data field of Modbus command is transmitted in 8-, 16-and 32-bit format.
The data for 16-bit registers is transmitted in high-byte first format. For example: 0x0A0B
0x0A, 0x0B. The data for 32-bit registers is transmitted as two 16-bit registers, and is high-word
first. For example: 0x0A0B0C0D
0x0A, 0x0B, 0x0C, 0x0D.