Unipi Technology Extension xS54 Modbus register map

Modbus RTU extension with 4 digital inputs, 5 relay outputs and 8 configurable analog inputs (voltage, current, resistance)

Official
90 registers
Modbus RTU
Revision 3 · 2026-11-10
Identity: firmware, serial number

Official: Written from the manufacturer's documentation, but not tested on a device yet. Check the map against the manufacturer's documentation before you write to a live device. Tested it? Report a test.

Download .mbmap.json Raw JSON View on GitHub Suggest a correction Report a problem

Communication

Protocol: Modbus RTU
Unit ID: 15
Serial: 19200 8N1 · 19200 baud, 8 data bits, none parity, 1 stop bit
Byte / word order: CDAB · bytes big-endian, words low first (word swap)
Addresses: 0-based

Connection values are defaults: the device may be configured differently.

Map

Registers: 75 holding registers, 15 coils
Groups: 11
Translation tables: 3
Revision: 3 · 2026-11-10
Added: 2026-11-10 (2026-11-10)
File: maps/unipi/xs54.mbmap.json · 16 KB · history
SHA-256: 6144c60f9b8bbf752f6d64d177cf387a64f0fa47bd2d1de805e94c114ff1a1ff
Manufacturer: www.unipi.technology

Device identity

What a tool can read to check that this map fits the connected device (SPEC.md section 4.7). Registers with a role are read like any other register.

Registers
Role	Register	Address	Type	Values
Firmware	Firmware version	holding 1000	uint16
Serial number	PCB serial number	holding 1005	uint32 CDAB

Sources and notes

Extension xS54 Modbus map · version 2.0
Holding registers, Coils and Description sheets

Source: Extension xS54 Modbus map v2.0, Unipi technology

Registers are 0-based. 32-bit values use word order CDAB (low word first). Defaults: slave address 15, 19200 bps, 8N1.
Registers marked Reserved in the manual are left out.

Area	Address	Type	Access	Unit	Scale	Description
HR	0	bool bit 0	R
HR	0	bool bit 1	R
HR	0	bool bit 2	R
HR	0	bool bit 3	R
HR	1	bool bit 0	RW
HR	1	bool bit 1	RW
HR	1	bool bit 2	RW
HR	1	bool bit 3	RW
HR	1	bool bit 4	RW
HR	2	float32 CDAB	R			Value in the unit of the selected input mode (V, mA or ohm)
HR	4	float32 CDAB	R			Value in the unit of the selected input mode (V, mA or ohm)
HR	6	float32 CDAB	R			Value in the unit of the selected input mode (V, mA or ohm)
HR	8	float32 CDAB	R			Value in the unit of the selected input mode (V, mA or ohm)
HR	10	float32 CDAB	R			Value in the unit of the selected input mode (V, mA or ohm)
HR	12	float32 CDAB	R			Value in the unit of the selected input mode (V, mA or ohm)
HR	14	float32 CDAB	R			Value in the unit of the selected input mode (V, mA or ohm)
HR	16	float32 CDAB	R			Value in the unit of the selected input mode (V, mA or ohm)
HR	18	bool bit 0	RW
HR	18	bool bit 1	RW
HR	19	uint32 CDAB	RW			Pulse counter; writable to reset
HR	21	uint32 CDAB	RW			Pulse counter; writable to reset
HR	23	uint32 CDAB	RW			Pulse counter; writable to reset
HR	25	uint32 CDAB	RW			Pulse counter; writable to reset
HR	27	bool bit 0	RW
HR	27	bool bit 1	RW
HR	27	bool bit 2	RW
HR	28	bool bit 0	RW
HR	28	bool bit 1	RW
HR	28	bool bit 2	RW
HR	28	bool bit 3	RW
HR	28	bool bit 4	RW
HR	29	bool bit 0	RW
HR	29	bool bit 1	RW
HR	29	bool bit 2	RW
HR	29	bool bit 3	RW
HR	29	bool bit 4	RW
HR	1000	uint16	R			Firmware version of the extension (raw number)
HR	1001	uint16 bits 0–7	R
HR	1001	uint16 bits 8–15	R
HR	1002	uint16 bits 0–3	R
HR	1002	uint16 bits 4–7	R
HR	1002	uint16 bits 8–15	R
HR	1003	uint16	R
HR	1004	uint16	R
HR	1005	uint32 CDAB	R
HR	1008	uint16	RW	ms		MasterWatchDog timeout; default 5000 ms
HR	1009	uint16	R			Reference voltage of the MCU (raw)
HR	1010	uint16	RW	ms	×0.1	Raw unit is 100 us; default 50 (5 ms)
HR	1011	uint16	RW	ms	×0.1	Raw unit is 100 us; default 50 (5 ms)
HR	1012	uint16	RW	ms	×0.1	Raw unit is 100 us; default 50 (5 ms)
HR	1013	uint16	RW	ms	×0.1	Raw unit is 100 us; default 50 (5 ms)
HR	1014	bool bit 0	RW
HR	1014	bool bit 1	RW
HR	1014	bool bit 2	RW
HR	1014	bool bit 3	RW
HR	1015	bool bit 0	RW
HR	1015	bool bit 1	RW
HR	1015	bool bit 2	RW
HR	1015	bool bit 3	RW
HR	1016	bool bit 0	RW
HR	1016	bool bit 1	RW
HR	1016	bool bit 2	RW
HR	1016	bool bit 3	RW
HR	1017	uint16	RW			Measurement type of the input; default 1
HR	1018	uint16	RW			Measurement type of the input; default 1
HR	1019	uint16	RW			Measurement type of the input; default 1
HR	1020	uint16	RW			Measurement type of the input; default 1
HR	1021	uint16	RW			Measurement type of the input; default 1
HR	1022	uint16	RW			Measurement type of the input; default 1
HR	1023	uint16	RW			Measurement type of the input; default 1
HR	1024	uint16	RW			Measurement type of the input; default 1
HR	1025	uint16 bits 0–12	RW			Applied after saving the configuration and restarting
HR	1025	bool bit 13	RW
HR	1025	bool bit 14	RW
HR	1026	uint16	RW			Slave address, 1-254; default 15
CO	0	bool	RW
CO	1	bool	RW
CO	2	bool	RW
CO	3	bool	RW
CO	4	bool	RW
CO	5	bool	R
CO	6	bool	R
CO	7	bool	R
CO	8	bool	R
CO	9	bool	RW
CO	10	bool	RW
CO	11	bool	RW
CO	1000	bool	RW			Clears the MWD reboot indication
CO	1002	bool	W
CO	1003	bool	W			Stores the current configuration so it is used at startup

Help improve this map

I tested it on a deviceReport whether it worked, even if you did not write the map.
Suggest a correctionEdit the file on GitHub; it opens a pull request.
Report a problemA wrong address, type, scale or byte order.
Read the formatWhat each key of the file means (SPEC.md).