Utility Help

This page is a Modbus TCP client and is excellent for verifying BASgatewayLX communication to Modbus devices. You can view coils and read/write registers via a web browser.

The five fields are:

Connect Status: When your PC connects to the BASgatewayLX, it first displays "Connected to target" then awaits a register access.
IP Address: (0.0.0.0 by default.) Enter IP address of a Modbus/TCP device to access. Enter 0.0.0.0 for Modbus RTU or ASCII device.
Slave Address: (1 by default.) Enter the address of a device to access.
Register Number: (1 by default.) Enter only the 3 least significant digits of the register address to access. The 2 most significant digits are automatically added and depend on whether you click the Read or Write button.
Value: This reads or writes values for the register in the Register Number field. When writing a value, match the number format of the selected radio button or an error appears in this field.
Status: If you read or write a register successfully, "Success" appears here and Value shows the result. If a register access is unsuccessful, the error is reported in the Value field.

Four radio buttons and one checkbox on the left specify the number format of the Value field:

0X:Coil: Check this if the addressed device is a Coil or Binary Output (0 or 1).
1X:Discrete Input: Use this to read a Binary Input (0 or 1).
3X:Input Reg: Use this to read a 16-bit register (raw-number format).
4X:Holding Reg: Use this to read or write a 16-bit register (raw-number format).
32-Bit: This displays a 32-bit value of a register pair (raw-number format) and enables the following four buttons.

Four radio buttons on the right specify the 32-bit number format:

Integer: Use this for a value with no fractional content.
Float: Use this for a single-precision floating-point value.
LOW:HIGH: Use this for Little Endian format (low word is in the base register and high word is in the next-higher register).
HIGH:LOW: Use this for Big Endian format (high word is in the base register and low word is in the next-higher register).

Read and Write buttons: Click one of these to complete the action.