Alicat M/MC/P/PC mass flow & pressure instruments

Register map(s) for this device, each at the trust rung it earned. Addresses are 0-based as on the wire; word order and scaling are only confirmed at the hardware-verified rung.

interop-verified

Read + decoded cleanly over a real network vs an independent third-party Modbus test server (transport and framing; reads are remapped into the server's register window, so the map's own addresses are NOT exercised). Does NOT prove word order/scaling against the actual device.

point	address (0-based)	type	scale
alarm_status	1295	U16	1
gas_number	1296	U16	1
device_status	1297	U32BE	1
setpoint_integer	1299	U32BE	1
valve_drive_integer	1301	U32BE	1
pressure_integer	1303	U32BE	1
secondary_pressure_integer	1305	U32BE	1
barometric_pressure_integer	1307	U32BE	1
temperature_integer	1309	U32BE	1
volumetric_flow_integer	1311	U32BE	1
mass_flow_integer	1313	U32BE	1
totalizer_1_integer	1315	U32BE	1
totalizer_2_integer	1317	U32BE	1
humidity_integer	1319	U32BE	1
alarm_status_float_mode	1345	U16	1
gas_number_float_mode	1346	U16	1
device_status_float_mode	1347	U32BE	1
setpoint	1349	F32BE	1
valve_drive	1351	F32BE	1
pressure	1353	F32BE	1
secondary_pressure	1355	F32BE	1
barometric_pressure	1357	F32BE	1
temperature	1359	F32BE	1
volumetric_flow	1361	F32BE	1
mass_flow	1363	F32BE	1
totalizer_1	1365	F32BE	1
totalizer_2	1367	F32BE	1
humidity	1369	F32BE	1

link settings as documented (unverified): RTU/TCP; default 19200 8N1; unit ID 1; FC 03,04,16; Alicat instruments require special firmware to support even parity. Default is no parity.

bench facts as documented (unverified)

terminals	8-Pin Mini-DIN, 6-pin Industrial Connectors, DB9, DB15, RJ45 Ethernet, M12 Ethernet
connector	8-Pin Mini-DIN, 6-pin Industrial Connectors, DB9, DB15, RJ45, M12
protocol notes	Reading undefined registers may return 65535 or ILLEGAL DATA ADDRESS exception.
serial register	1093
firmware register	1089
identification notes	Registers 1087-1088 (0-based) hold a fixed value 1067320907 to verify byte order.
doc revision	Rev 7, November 2024

generated by gemini:gemini-3.5-flash · harvested from https://documents.alicat.com/manuals/DOC-MANUAL-MODBUS.pdf (Alicat Scientific); manual-faithful — the document's claims, panel risk: ELEVATED — panel is not confident; proved interop-verified on 2026-06-10 · recorded 2026-06-10

The trust ladder

Each rung states what it proved and what it did not. Gray until proven; green is earned by hardware only.

generated — A prompt produced it. Unproven — anyone can regenerate this.
structure-verified — Decode path is structurally sound (addresses, widths, finite values). Does NOT prove word order or scaling.
interop-verified — Read + decoded cleanly over a real network vs an independent third-party Modbus test server (transport and framing; reads are remapped into the server's register window, so the map's own addresses are NOT exercised). Does NOT prove word order/scaling against the actual device.
simulator-verified — Decoded correctly against a protocol emulator seeded with known-true values — catches word-order/scaling errors vs the emulator, not the physical device.
hardware-verified x1 — Matched a real device with operator-attested readings as ground truth — the only rung that confirms word order + scaling on the wire.

Have a device that isn't here? Upload its register map — generation is free, and the connector earns its rung by being proven, not claimed.

Need it proven on your own device? Hardware verification — if it doesn't verify, you don't pay.

Building a platform? License the verified library — machine-readable maps, firmware matrix, API access.