GT01

What type of component is this?

This is a compact GT Series programmable display, commonly used as an operator interface in industrial automation panels. The GT01 is intended for displaying machine information and allowing interaction with connected control equipment.

What communication protocol is associated with this display?

The display is associated with Modbus RTU slave communication. In this mode, an external device sends commands to the display and the display responds according to the command received.

Which Modbus function codes are used with this unit?

The GT Series Modbus RTU slave manual lists function codes for reading internal relay status, reading data registers, writing a single internal relay, writing one word to a data register, writing multiple internal relays, and writing multiple data registers.

What communication settings are typically used?

The unit can operate with baud rates of 9600, 19200, 38400, 57600, and 115200 bps. Communication uses 8 data bits, with parity set to odd, even, or none depending on the connected device configuration.

What is the valid unit number range for Modbus communication?

The GT unit number range is 1 to 247 for normal communication. Address 0 may be used for broadcast write functions, but no response is returned in broadcast mode.

What internal memory areas are used by the display?

The display uses internal memory areas called GDT and WGR. GDT is used for word-based data registers, while WGR is used for bit-based internal relays.

What are GDT registers used for?

GDT registers are word devices used to handle data in word units. The documented GDT range is GDT0 to GDT2047, with special clock data registers also listed in the GDT9080 to GDT9086 range.

What are WGR relays used for?

WGR relays are bit devices used for internal relay functions. They are suited to on/off status handling, internal flags, and bit-level interaction with the operator display.

What is the maximum Modbus command or response length?

The maximum command and response length stated for the GT Series Modbus RTU format is 512 bytes.

How is error checking handled in Modbus RTU communication?

Error checking is handled using CRC-16. The calculated 16-bit CRC value is appended to the end of the message in lower-byte then higher-byte order.

Which serial interfaces are referenced for GT Series connection diagrams?

The GT Series connection information references RS232C, RS422, and RS485 connection arrangements. The exact connection method depends on the external device and the communication configuration used.

What should be checked if the display does not respond to a Modbus command?

Common checks include the communication cable wiring, matching unit number, baud rate, parity setting, CRC-16 value, and whether the command interval is within the expected timing. The display may ignore commands with transmission errors or an address that does not match its configured unit number.