ABB TPU2000 Technical Manual page 270

TPU2000/2000R Modbus/Modbus Plus/ Modbus TCP/IP Automation Guide
3-Download Data: These commands edit the TPU2000 data. The TPU2000 responds with an ACK after the successful
receipt of each data message packet. This can be seen in the figure below.
Master
Message Packet Checksum: This checksum is different than the checksum associated with every incom message packet. The
value of the checksum is contained in a two byte integer and is the summation of all message bytes (1/1 + 1/2 + 1/3 + 2/1 +
2/2 + ...) for the command. The only exception is that the checksum message bytes are not included in the summation.
Example (3 3 1 command): (values are hex equivalent of the ASCII)
1/1 = hex 05
1/2 = hex 31
1/3 = hex 04
2/1 = hex 00
2/2 = hex 01
2/3 = hex 44
Command Set Summary
Inst
3
3
3
3
3
3
3
3
3
3
Master
Figure 8 - Upload Data Communication Flow
Command
Figure 9 - Download Data Communication Flow
3/1 = hex 44
3/2 = hex 00
3/3 = hex 00
4/1 = hex 00
4/2 = hex 00 <-- checksum high byte
4/3 = hex C3 <-- checksum low byte
Cmd Subcmd
0 n
1 n
2 n
3 n
4 n
5 n
6 n
7 n
8 n
9 n
Command
Data
.
.
.
Data
Data
ACK
Data
ACK
Data
.
.
.
Data
ACK
Definition
Status Commands
Transmit Settings Commands
Transmit Settings Commands
Transmit Meter/Record Commands
Load Profile/Record Commands
Transmit Meter Commands
Relay Commands
DPU2000
DPU2000
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