
Appendix C: Modbus Protocol Implementation Conformance Statement
RTU Open v3
Carrier Proprietary and Confidential
CARRIER CORPORATION ©2016
Integration Guide
All rights reserved
48
Unsigned Integer (UINT)
0 - 65535
3 – Read Holding Register
6 – Preset Single Register
16 – Preset Multiple Register
Signed Integer (SINT)
-32768 - 32767
3 – Read Holding Register
6 – Preset Single Register
16 – Preset Multiple Register
Discrete Input (DI)
0 = Off, 1 = On
2 – Read Input Status
Discrete Output (DO)
0 = Off, 1 = On
1 – Read Coil Status
5 – Force Single Coil
15 – Force Multiple Coils