Overview
How to connect
- Host
modbus-sendbox.electroman.by- Port
5020- Unit ID
1..10(slave 10 - input registers only)- Functions
1, 2, 3, 4, 5, 6, 16- anything else is rejected
Check connection
The server runs 5 control reads of the selected slave over Modbus-TCP (loopback) and reports RTT. This also checks TCP, the protocol and the register map. The probe writes nothing and never hits the journal.
Server counters
- Active connections
- -
- Requests / s
- -
- Errors / s
- -
- Total requests
- -
- Total errors
- -
- Uptime
- -
Rates are averaged over a sliding window. Errors include exception-code responses and requests swallowed by timeout injections.
Data formats per slave
| Unit ID | HR/IR format | HR | IR | CL | DI |
|---|---|---|---|---|---|
| 1 | uint16 | 1..1024 | 1..1024 | 1..64 | 1..64 |
| 2 | uint32 ABCD | 1,3,…,1023 | 1,3,…,1023 | 1..64 | 1..64 |
| 3 | uint32 CDAB | 1,3,…,1023 | 1,3,…,1023 | 1..64 | 1..64 |
| 4 | uint32 BADC | 1,3,…,1023 | 1,3,…,1023 | 1..64 | 1..64 |
| 5 | uint32 DCBA | 1,3,…,1023 | 1,3,…,1023 | 1..64 | 1..64 |
| 6 | float ABCD | 1,3,…,1023 | 1,3,…,1023 | 1..64 | 1..64 |
| 7 | float CDAB | 1,3,…,1023 | 1,3,…,1023 | 1..64 | 1..64 |
| 8 | float BADC | 1,3,…,1023 | 1,3,…,1023 | 1..64 | 1..64 |
| 9 | float DCBA | 1,3,…,1023 | 1,3,…,1023 | 1..64 | 1..64 |
| 10 | uint16 | - | 1..268, 300..301 | - | - |
Slave 10 serves input registers only. Addresses 300..301 carry the Unix timestamp (uint32 ABCD), the rest of its IR is uint16. Time zone metrics live in the «Time zones» section. A 32-bit value occupies two registers (value addresses 1, 3, …, 1023).
Live register state, behavior setup, error injections and the event journal live in the neighbouring sections.
The server is free and stays that way. We are raising money for a test bench with real instruments to run every ModbusToolkit build against.