Allen-Bradley 1794-IT8, User Manual

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4–4 Writing Configuration to and Reading Status from your Module with a Remote I/O Adapter
Publication 1794-6.5.7 – April 1997
Read programming moves status and data from the thermocouple
input module to the processor’s data table. The processor’s user
program initiates the request to transfer data from the
thermocouple/mV input module to the processor.
The following read and write words and bit/word descriptions
describe the information written to and read from the
thermocouple/mV input module. The module uses up to 11 words of
input image and up to 3 words of output image. Each word is
composed of 16 bits.
Thermocouple/mV Input Module (1794-IT8) Image Table Mapping
Module Image
I/O Image
Input Data Channel 0
Input Data Channel 1
Input Data Channel 2
Input Data Channel 3
Input Data Channel 4
Input Data Channel 5
Input Data Channel 6
Input Data Channel 7
Underrange
Calibration Mask
Thermocouple Type
Input Size
Output Size
0 to 3 Words
1 to 11 Words
Reserved
Overrange
Calibration Status
Thermocouple Type
Configuration
Thermocouple/mV Input Module (1794-IT8) Read
Decimal Bit 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
Octal Bit 17 16 15 14 13 12 11 10 07 06 05 04 03 02 01 00
Read Word 0 Reserved
1 Channel 0 Input Data
2 Channel 1 Input Data
3 Channel 2 Input Data
4 Channel 3 Input Data
5 Channel 4 Input Data
6 Channel 5 Input Data
7 Channel 6 Input Data
8 Channel 7 Input Data
Reading Data From Your
Module
Mapping Data for the
Analog Modules