Rockwell Automation 1794-IP4 Series B FLEX I/O PULSE COUNTER User Manual User Manual

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4–2

Writing Configuration to and Reading Status from Your Module with a Remote I/O Adapter

Publication 1794ĆUM016B-EN-P - August 2002

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 Pulse Counter
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 Pulse
Counter module to the processor.

The following read and write words and bit/word descriptions
describe the information written to and read from the Pulse Counter
module. The module uses up to 11 words of input data and up to 3
words of output data. Each word is composed of 16 bits.

Pulse Counter Module (1794ĆIP4) Image Table Mapping

Module Image

I/O Image

Input Size

Output Size

0 to 3 Words

1 to 10 Words

Counter 00 - 16-bit period measurement or low word of 32Ćbit period measurement for channel 0

Code for identification of software version

Control Word 0 - Sets the measure function

Control Word 2 - sets the start of a new measurement

Control Word 1 - Sets the clock frequency and period multiple

Counter 01 - pulse counter for channel 0 or high word of 32Ćbit period measurement

Counter 10 - 16-bit period measurement or low word of 32Ćbit period measurement for channel 1

Counter 11 - pulse counter for channel 1 or high word of 32Ćbit period measurement

Counter 20 - 16-bit period measurement or low word of 32Ćbit period measurement for channel 2

Counter 21 - pulse counter for channel 2 or high word of 32Ćbit period measurement

Counter 30 - 16-bit period measurement or low word of 32Ćbit period measurement for channel 3

Counter 31 - pulse counter for channel 3 or high word of 32Ćbit period measurement

Readback of Control word 2 or

Reserved

RD0

RD1

RD2

RD3

ReadingData From Your

Module

MappingData for the

Module