Register Usage; Rw 1-Bit - ABB AquaMaster 3 Manual

AquaMaster 3
Electromagnetic flowmeter

1.3 Register Usage

This section provides further information and worked examples of MODBUS protocol messages,
application data units (ADUs) and their responses for each of the Register ranges corresponding to
AquaMaster 3 data types.
Note: MODBUS data model register addressing starts from XXXX1 but within the MODBUS protocol
data unit (PDU) addressing starts from XXXX0.
Register addresses shown in the Register allocation tables (Appendix A) are MODBUS data model
register addresses.

1.3.1 RW 1-Bit

Read/Write access to single bit types.
Read Coils 1 to 14
Read all RW 1-Bit items
Request Message
Address
Function
Starting Address Hi
Starting Address Lo
Quantity of Inputs Hi
Quantity of Inputs Lo
CRC
CRC
*Coils 1,6,7,9,11 = 1
*Coils 2,3,4,5,8,10,12,13,14 = 0
Write Single Coil 3
var54: Display Net Total = ON
Request Message
Address
Function
Output address Hi
Output Address Lo
Output Value
Output Value
CRC
CRC
MODBUS Tables Supplement COI/FET2XX/MOD/TBL-EN
(Hex) Response Message
01 Address
01 Function
00 Byte count
00 Outputs status 00008-00001*
00 Outputs status 00014-00009*
0E CRC
BD CRC
CE
(Hex) Response Message
01 Address
05 Function
00 Output Address Hi
02 Output Address Lo
FF Output Value
00 Output Value
2D CRC
FA CRC
(Hex) Error Message
01 Function
01 Exception Code
02
61
05
50
6F
(Hex) Error Message
01 Function
05 Exception Code
00
02
FF
00
2D
FA
MODBUS Protocol
(Hex)
81
Exception Code
(Hex)
85
Exception Code
4