Block write – Watlow CLS200, MLS300 and CAS200 User Manual

Page 19

Chapter 1: ANAFAZE/AB Protocol

Communications Specification 13

Block Write

This section describes the block write command.

This example shows the block write command the master sends, the
controller's responses, and the master's acknowledgment:

Situation: Write setpoint of 100 to loop 6.

•

1 setpoint 2 bytes per setpoint = 2 bytes to address x01CA (x01C0 +

xA, a 10-byte offset).

•

Character values are represented in hexadecimal.

•

The sender is device address 0.

•

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

•

The software sends transaction number 00.

Here's a picture of the write command:

The controller sends a DLE-ACK:

x10 02 08 00 08 00 00 00 CA 01 E8 03 10 03 3A

DLE

STX

DST (Destination Device Address)

SRC (Source Device Address)

Command (block write)

Placeholder for status byte

Transaction number

Data table address
LSB first; x01CA = setpoint for loop

Data: 100 converts to 1000 = x03E8

(assuming the precision for loop 6 is –1)

DLE

ETX

BCC value

x10 06

ACK

DLE