Sykel Modbus Simulator
Build the other end of the wire.
Simulate up to 100 Modbus devices with editable data, realistic fault injection, and communication visibility—before hardware is available or when it needs to misbehave on purpose.
Make testing repeatable
Give every master something real enough to trust.
- Up to 100 simulated devices on one shared connection
- Coils, discrete inputs, holding registers, and input registers
- Auto-changing values and editable cells
- Response delay, dropped response, corrupted checksum, and busy simulation
- Serial RTU/ASCII, TCP, UDP, and RTU-over-socket transports
Useful in a lab and on a bench
Model the address space your device will expose, then use a live master to validate mappings, polling cadence, write behavior, and UI handling long before a physical unit arrives.
Considering a Modbus Slave alternative?
Use an independent simulator on macOS, Linux, or Windows, with the files and familiar workflow concepts that matter on a real test bench.
Faults with intent
Simulate response delay, skipped responses, corrupted checksums, and exception 06 busy responses per window. The errors are visible and repeatable—useful for validating error handling instead of hoping it occurs in the field.