Coilware · WEB-001rev. 05 · 19.05.2026sheet 01/08scale 1:1
COILWARE · INDUSTRIAL COMMS

Modern software for
industrial communications.

Modern diagnostic and engineering tools for industrial communications - starting with Modbus.

Join the beta See Coilware Modbus 30-day trial · perpetual licence · £179
Modbus Tools - Default workspace
Modbus Tools/Modbus TCP ClientSE
Polling · 500 ms
Search registers
FCAddressNameDisplay asValueUnitTrend
FC03Voltages - line to neutral40001 – 40006
FC0340001Voltage L1–NF32230.48V
FC0340003Voltage L2–NF32229.72V
FC0340005Voltage L3–NF32230.94V
FC03Power & energy40013 – 40020
FC0340013Active Power TotalF329813.75W
Byte-order decode · 2-register FLOAT32
OrderFloat32UInt32Int32
ABCD9813.751,176,065,7931,176,065,793
CDAB1.42e+141,459,701,2731,459,701,273
BADC1.02e-23424,018,263424,018,263
DCBA3.95e-3822,485,31822,485,318

Highlighted orders decode to a plausible value - click to apply.

Register · 40013
Function code
0x03 · Read Holding Registers
Word count
2
Display type
F32 · ABCD
Polled
every 500 ms
FC0340015Power FactorF320.97-
FC0340017FrequencyF3250.05Hz
FC0340019kWh ImportU32184,272Wh
FC04Line currents30001 – 30006
FC0430001Current L1F3214.72A
FC0430003Current L2F3213.91A
FC0430005Current L3F3214.07A
FC01Relay outputs00001 – 00002
FC0100001Relay K1 - TripBit0--
FC0100002Relay K2 - AlarmBit1--
FC02Interlocks10001 – 10002
FC0210001Door interlockBit1--
FC0210002Earth-fault inputBit0--
Connected·tcp://10.34.18.221:502·RTT 8 ms·41 ops/sWorkspaceDefault·v0.9.4
SUPPORTED · MODBUS, ALL THREE TRANSPORTS
Modbus TCPsupported
Modbus RTUsupported
Modbus ASCIIsupported
The thesis

The protocols are fine.
The tools around them are not.

The small utilities every engineer reaches for - Modbus scanners, serial sniffers, register pokers - look and feel like they did fifteen years ago. They work. They're also clunky, ugly, and well below the standard of any other professional software in 2026.

We're working engineers, and Coilware exists to fix that - better versions of the tools we already use every day, built to the standard the rest of our software stack hit a decade ago.

Inside Coilware Modbus

Diagnostic tools, designed.

Full feature tour
40001Voltage L1230.42V
40003Voltage L2229.88V
40013Power Tot.9821.4W
40017Frequency50.01Hz
01

Live register table

Holding, input, coil, discrete - typed, scaled, annotated, polled. Edit cells in place. Watch values as they change.

TX 12:04:18.214 01 03 9C 41 00 02 6C 79
RX 12:04:18.227 01 03 04 43 66 6B 85 8A 14
TX 12:04:18.314 01 03 9C 43 00 02 0D B8
RX 12:04:18.327 01 03 04 43 65 E1 48 DA 92
02

Frame inspector

Every TX/RX frame, decoded. CRC validated. Function code described. The Wireshark you don't have to install.

43666B85
ABCD230.42
CDAB−1.30e13
BADC3.85e−37
03

Byte-order decoder

Paste 4 hex bytes. See every endianness interpretation side-by-side. Stop guessing whether it's ABCD or CDAB.

1 v = client.read_float(40001)
2 if v > 253:
3   client.write_coil(1, True)
4   log("trip")
04

Scripted polling

Python macros with a pre-bound client object. Conditional writes. Trigger reads on register thresholds. Schedule diagnostics overnight.

coilware-modbus18.4 MB
coilware-modbus.exe19.1 MB
coilware-modbus.app22.7 MB
single binary · no admin install
05

Single binary

No installer. No admin rights. Drop the executable on a thumb drive and run it on the locked-down plant laptop.

FREE EBOOK · COMING SOON

The Modbus Debugging Field Manual.

A free, practical guide to debugging Modbus on real plant networks - exception codes, byte-order traps, and the fixes that actually work. We're writing it now. Join the list and we'll email you the day it ships.

Join the waitlist free · no upsell
COILWARE · FM-01
TheModbusDebuggingFieldManual
Edition 1Coming 2026
Coilware Modbus · v0.9.4-BETA

Twenty perpetual licences.
Honest feedback in exchange.

We're opening a limited beta in June 2026 - and taking applications now. First twenty engineers get a free perpetual licence in exchange for bug reports, feature requests, and the occasional grumpy email.

Free perpetual licences20
Beta opensJune 2026
ApplicationsOpen now
Price at launch£179 one-time
Refund policy30 days, no questions