Examples:
MBA= ,1,2,12,array[]
Request the status of coils 2-13 (result is stored in array[])
MG@OUT[1002]
Requests the status of coil 2 (result is transmitted via serial port or
ethernet)
Packets
The command MBA=,1,2,10,array[] results in the following packets being sent, when one RIO is the master,
and another RIO is the slave, communicating over handle A, port 502(Modbus). Assume digital outputs, in
descending order from 15-0 are: 0,1,1,1,0,0,1,1,0,0,1,1,0,1,1,1
Request
Response
Field Name
(hex)
Field Name
(hex)
Function 01
Function
01
Starting Address High
00
Byte Count
02
Starting Address Low
02
Outputs Status 9-2
CD
Quantity of Outputs High
00
Outputs Status 13-10
0C
Quantity of Outputs Low
0C
1
st
Byte of Response Word
bit 7 6 5 4 3 2 1 0
Coil
# 9 8 7 6 5 4 3 2
Value 1 1 0 0 1 1 0 1
2
nd
Byte of Response Word
bit 15 14 13 12 11 10 9 8
Coil
# X X X X 13 12 11 10
Value 0 0 0 0 1 1 0 0
Note: bits in the response marked 'X' are not valid coil response data, but are instead 0's that fill the
remainder of the byte
On the master RIO, array[0]=205 and array[1]=12 after the MBA= ,2,2,12,array[]command is issued
18 Chapter 3 Communication
RIO-47xxx
