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Mapping Device Control Block Bits to I/O Scanner Entry Numbers

Goals and Symptoms

To inform users the incorrect IO scanner device control block bit map in Modicon Quantum with Unity Ethernet Network Modules User Manual.

Facts and Changes

Effected Documentation: Modicon Quantum with Unity Ethernet Network Modules User Manual
Related Product part number: 140NOE77101/11

· To use %MDx.4 as device control block, the double word to enable/disable each I/O scanner entry is described below:

Register text text text text text text text text text
Double
Word
%MDx[0]
Table
Entry #
1 2 3 4 5 6 7 8
text Bit 31 30 29 28 27 26 25 24
text Table
Entry #
9 10 11 12 13 14 15 16
text Bit 23 22 21 20 19 18 17 16
Double
Word
%MDx[1]
Table
Entry #
17 18 19 20 21 22 23 24
text Bit 15 ** 14
**
13
**
12
**
11
**
10
**
9
**
8
**
text Table
Entry #
25 26 27 28 29 30 31 32
text Bit 7
**
6
**
5
**
4
**
3
**
2
**
1
**
0
**
text Table
Entry #
33 34 35 36 37 38 39 40
text Bit 31 30 29 28 27 26 25 24
text Table
Entry #
41 41 43 44 45 46 47 48
text Bit 23 22 21 20 19 18 17 16
text Table Entry 49 through 112 text text text text text text text text
Double
Word
%MDx[4]
Table
Entry #
113 114 115 116 117 118 119 120
text Bit 15 14 13 12 11 10 9 8
text Table
Entry #
121 122 123 124 125 126 127 128
text Bit 7 6 5 4 3 2 1 0
    • NOTE**: it is the bit of MDx[1] used for I/O scanner table entry 17 to 32, not MDx[0].
      Bit number: Bit 0 is a low bit counting from right side.

      Example:
      If users configure %MD1:4 as device control block, %MD1[0] bit 31 can enable/disenable I/O scanner table entry 1. %MD1[1] bit 15 can enable/disenable I/O scanner table entry 17.

· To use %MDx.4 as device control block, users also can use single registers to enable/disable each I/O scanner entry as mapped below:

Register text text text text text text text text text
%MWx+1 Table
Entry #
1 2 3 4 5 6 7 8
text Bit 15 14 13 12 11 10 9 8
text Table
Entry #
9 10 11 12 13 14 15 16
text Bit 7 6 5 4 3 2 1 0
%MWx+2 Table
Entry #
17 18 19 20 21 22 23 24
text Bit 15 14 13 12 11 10 9 8
text Table
Entry #
25 26 27 28 29 30 31 32
text Bit 7 6 5 4 3 2 1 0
%MWx+3 Table
Entry #
33 34 35 36 37 38 39 40
text Bit 15 14 13 12 11 10 9 8
text Table
Entry #
41 41 43 44 45 46 47 48
text Bit 7 6 5 4 3 2 1 0
Table Entry 49 through 112 text text text text text text text text text
%MWx+8 Table
Entry #
113 114 115 116 117 118 119 120
text Bit 15 14 13 12 11 10 9 8
text Table
Entry #
121 122 123 124 125 126 127 128
text Bit 7 6 5 4 3 2 1 0

    • Bit number: Bit 0 is a low bit counting from right side.
      Example:
      If users configure %MD1:4 as device control block, %MW2 bit 15 can enable/disenable I/O scanner table entry 1. %MW3 bit 15 can enable/disenable I/O scanner table entry 17.

Causes and Fixes

Schneider will correct the documentation -- Modicon Quantum with Unity Ethernet Network Modules User Manual to match the current implementation.

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