
Appendix E: Backward Compatibility
62 (70)
E.4
Network Specific — Modbus-TCP
E.4.1
Modbus Registers
Rearrangements have been made in the Modbus register map, because process data sizes
have been increased to 1536 bytes in each direction. An existing PLC configuration need to be
changed to use the new addresses.
No difference on the application side.
Contents
30-series Modbus Address
40-series Modbus Address
Holding Registers (4x)
Read Process Data
0000h-00FFh
0000h-02FFh
Write Process Data
0100h-01FFh
0800h-0AFFh
Process Active Timeout
0203h
1003h
Enter/Exit Idle Mode
0204h
1004h
ADI Number 1
0210h-021Fh
1010h-101Fh
ADI Number 2
0220h-022Fh
1020h-102Fh
ADI Number 3839
FFF0h-FFFFh
Input Registers (3x)
Write Process Data
0000h-00FFh
0000h-02FFh
Diagnostic Event Count
0100h
0800h
Diagnostic Event #1
0101h
0801h
Diagnostic Event #2
0102h
0802h
Diagnostic Event #3
0103h
0803h
Diagnostic Event #4
0104h
0804h
Diagnostic Event #5
0105h
0805h
Diagnostic Event #6
0106h
0806h
Coils (0x)
Read Process Data
0000h-0FFFh
0000h-2FFFh
Discrete Inputs (1x)
Write Process Data
0000h-0FFFh
0000h-2FFFh
E.4.2
BOOL arrays
Process data mapped BOOL arrays are not compressed to bit-fields on the network in the 40-
series, but handled as a normal 8-bit datatype. To create bit-arrays in the 40-series, use the
new datatypes BITx instead.
Anybus
®
CompactCom
™
40 Modbus-TCP
®
Transparent Ethernet Network Guide
SCM-1202-022 1.1