Allen-Bradley 1794-IE8 Series B

3–6 Module Programming
Publication 17946.5.2 - May 1996
The data returned from the analog-to-digital converter in the module
is 12-bit resolute. This value is left-justified into a 16-bit field,
reserving the most significant bit for a sign bit.
14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
11 10 09 08 07 06 05 04 03 02 01 00
S
S
14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
10 09 08 07 06 05 04 03 02 01 00
S
S
14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
11 10 09 08 07 06 05 04 03 02 01 00
0*
A/D Unipolar Data
Analog Value
A/D Bipolar Data
Analog Value
D/A Data
Analog Value
⇓⇓ ⇓⇓ ⇓⇓⇓⇓⇓⇓⇓⇓
⇓
⇓⇓ ⇓⇓ ⇓⇓⇓⇓⇓⇓⇓⇓
⇓⇓ ⇓⇓ ⇓⇓⇓⇓⇓⇓⇓⇓
* = Always positive
Output
Input
Refer to Appendix C for a table of values for various current and
voltage modes.
Appendix C also includes an example of scaling.
In this chapter, you learned how to program your programmable
controller. You were given sample programs for your PLC-3 and
PLC-5 family processors.
Analog Data Format
Chapter Summary