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Examples, Block read – Watlow CLS200, MLS300 and CAS200 User Manual

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10 Communications Specification

Chapter 1: ANAFAZE/AB Protocol

Examples

The host software sends two kinds of commands: block reads and block
writes. This section shows examples of both commands.

NOTE

If you read data from a loop set to SKIP, the controller will

send an empty packet for that loop.

This section does not show how to calculate the error check value
included with every packet. For help calculating the error check value,
see the section on BCC or CRC earlier in this chapter.

Block Read

This example shows the block read command the host software sends,
the controller’s responses, and the software's acknowledgment.

Situation: Read process variables for loops 1 to 8.

8 process variables 2 bytes each = 16 bytes from data table address

x0280.

Character values are represented in hex.

The sender is device address 0.

The destination is device address 8 (controller address 1).

The software sends transaction number 00.