286 MODBUS – CODESYS 2
WAGO-I/O-SYSTEM 750
750-8207 PFC200 CS 2ETH RS 3G
Manual
Draft version 1.2.1 from 2017-09-13, valid from FW Version 02.06.20(09)
10.4.3 MODBUS Registers
WAGO-specific registers are implemented in the last MODBUS-relevant address
area; this simplifies the reading of certain system and MODBUS information, as
well as configuration.
The MODBUS address area reserved for these registers ranging from the
MODBUS starting address of 4096 (0x1000) up to the MODBUS end address of
12287 (0x2FFF), without any allocation to the IEC 61131 address area. These
registers can be queried using the register read services FC3, FC4 and FC23
and with the register write services FC6, FC16 and FC23. A detailed description
of the individual registers is given in the section “WAGO MODBUS Registers”.
10.4.4 MODBUS Mapping
10.4.4.1 MODBUS Mapping for Write Bit Services FC1, FC2
The table below outlines the mapping for the MODBUS-reading, bit-oriented
services:
•
FC1 – Read Single Coil,
•
FC2 – Read Discrete Inputs.
Table 206: MODBUS Mapping for Read Bit Services FC1, FC2
MODBUS Address
(hexadecimal values
in parentheses)
IEC 61131
Address
Description
0 … 6143
(0x0000 … 0x17FF)
%IX1000.0 …
%IX1383.15
MODBUS Output:
6144 PFC input bit variables in the first
384 registers/words (768 bytes) of the
2kB MODBUS output process image in
the PII.
Note: In this area, the read bit services
return the content from the bit-addressed
PII.
6144 … 12287
(0x1800 … 0x2FFF)
%QX1000.0 …
%QX1383.15
MODBUS Input:
6144 PFC output bit variables in the first
384 registers/words (768 bytes) of the 2
kB MODBUS-input process image in the
PIO.
12288 … 65535
(0x3000 … 0xFFFF)
%MX0.0 …
%MX3327.15
Maximum bit-addressable flag area:
53248 bit flags (6.5 kB);
the actual addressable flag area
depends on the current memory
arrangement in CODESYS.
