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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