Reading Data From Your Module; Mapping Data For The Module; Incremental Encoder Module (1794-Id2) Image Table Mapping - Allen-Bradley FLEX I/O 1794-ID2 User Manual

4–2 Writing Configuration to and Reading Status from Your Module with a Remote I/O Adapter
Reading Data From Your
Module
Mapping Data for the
Module
I/O Image
Input Size
1 to 8 Words
Output Size
0 to 4 Words
Publication 1794-6.5.15 – December 1998
During normal operation, the processor transfers from 1 to 4 words
to the module when you program a BTW instruction to the module's
address.
Read programming moves status and data from the frequency input
module to the processor's data table in one I/O scan. The processor's
user program initiates the request to transfer data from the
incremental encoder module to the processor.
The following read and write words and bit/word descriptions
describe the information written to and read from the incremental
encoder module. The module uses up to 8 words of input data and up
to 4 words of output data. Each word is composed of 16 bits.

Incremental Encoder Module (1794-ID2) Image Table Mapping

R PR1 PR0 S1 S0
Store 0 – Stored Counter Value on channel 0
Store 1 – Stored Counter Value on channel 1
Code for identification of software version
Channel 0 Control Word – Sets the function of counter 0
Channel 1 Control Word – Sets the function of counter 1
Channel 0 Preset – value to load or compare with counter 0
Preset 1 – value to load or compare with counter 1
Module Image
C1 C0 G1 Z1 B1 A1
Channel 0 – current counter value
Channel 1 – current counter value
Channel 0 – Counter word readback
Channel 1 – Counter word readback
G0 Z0 B0 A0