Mastervolt MasterBus - Example Writing Request

EN / MasterBus – Modbus Interface / September 2014 7
6.5.2 Example writing request
This is an example of a request to WRITE to the
variable with :
 Monitoring (TabNr = 0);
 Variable index (Index = 1);
 MasterBus device IDAL = 0x0E ID;
 MasterBus device IDB = 0x0217C1.
Request example
Variable Value Range
Bus address 0x01 [1..247]
Function code 0x17 Fixed
Read Starting Address Hi 0x00 Fixed
Read Starting Address Lo 0x00 Fixed
Quantity to Read Hi 0x00 Fixed
Quantity to Read Lo 0x06 Fixed
Write Starting Address Hi 0 Fixed
Write Starting Address Lo 1 0 = read / 1 = write
Quantity to Write Hi 0x00 Fixed
Quantity to Write Lo 0x06 Fixed
Write Byte Count (Fixed) 0x0C Fixed
IDAL 0x0E [0..31]
IDB Hi 0x02 [0..3]
IDB Mi 0x17 [0..255]
IDB Lo 0xC1 [0..255]
TabNr Hi 0x00 Fixed
TabNr Lo 0x00 [0..3]
Index Hi 0x00 [0..255]
Index Lo 0x01 [0..255]
Value Lo (Float IEEE 754) 0x00
[0..255]
Value Mi 0x00
[0..255]
Value Hi 0x80
[0..255]
Value Exponent 0x3F
[0..255]
CRC Lo 0x85
[0..255]
CRC Hi 0xFA
[0..255]
Response example
Variable Value Range
Bus address 0x01 [1..247]
Function code 0x17 Fixed
Byte Count(Fixed) 0x0C Fixed
IDAL 0x0E [0..31]
IDB Hi 0x02 [0..3]
IDB Mi 0x17 [0..255]
IDB Lo 0xC1 [0..255]
TabNr Hi 0x00 Fixed
TabNr Lo 0x00 [0..3]
Index Hi 0x00
[0..255]
Index Lo 0x01
[0..255]
Value Lo (Float IEEE 754) 0x00
[0..255]
Value Mi 0x00
[0..255]
Value Hi 0x80
[0..255]
Value Exponent 0x3F
[0..255]
CRC Lo 0x94
[0..255]
CRC Hi 0xC1
[0..255]