Using bcd data input – Rockwell Automation 2706-LV2P_LV2R_LV4P_LV4R DL40 PLUS USER MANUAL User Manual
Page 85
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Parallel Port Communications
7–5
Publication 2706-6.1
Using BCD Data Input
You can use the 16 data lines to input BCD data. The BCD
numbering system uses a group of four binary digits to represent a
single decimal digit. The following table shows the BCD value of
each data line.
Data Line
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
Data Line Value
8000
4000
2000
1000
800
400
200
100
80
40
20
10
8
4
2
1
For example, assume the following logic levels appear for each data
line. Adding the values of the individual data lines provides the value
being entered, 5545.
Data Line
Logic Level
Value
D0
D1
D2
D3
D4
D5
D6
D7
D8
D9
D10
D11
D12
D13
D14
D15
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
Logic 1
Logic 0
Logic 1
Logic 0
Logic 0
Logic 0
Logic 1
Logic 0
Logic 1
Logic 0
Logic 1
Logic 0
Logic 1
Logic 0
Logic 1
Logic 0
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
1
0
4
0
0
0
40
0
100
0
400
0
1000
0
4000
0
Sum of all values
5545