Rockwell Automation 900 Temperature Controller Communications Functions - Series B - Manual (Page 72)

Publication 900-UM004D-EN-E - July 2010
4-14 Modbus Communications Procedure
Example Command and Response
The following example shows the command/response when writing the
Upper-Limit Alarm 1 and Lower-Limit Alarm 1 parameters. (In this case, the
slave address is H’01.)
• Four-Byte Mode
Upper-Limit Alarm 1
· Address: H’010A Write data: H’000003E8 (when 1,000)
Lower-Limit Alarm 1
· Address: H’010C Write data: H’FFFFFC18 (when − 1,000)
Figure 4.13
• Two-Byte Mode
Upper-Limit Alarm 1
· Address: H’2105 Write data: H’03E8 (when 1,000)
Lower-Limit Alarm 1
· Address: H’2106 Write data: H’FC18 (when − 1,000)
Figure 4.14
01 10 01 0A 00 04
01 0A 00 04
00 00 03 E8 FF FF FC 18 8D E9(CRC-16)
01 10
08
E0 34(CRC-16)
Command:
Response:
Command:
Response: 01
01 10
10 21 05 00 02
03 E8
5BF5 (CRC-16)
21 05 00 02 04 FC 18 66BB (CRC-16)