User guide

A.6 ■ Appendix Watlow Series 97

Example: Read register 0 (model number) of the controller at address 1.

Sent: 01 03 00 00 00 01 84 0A

Received: 01 03 02 00 61 79 AC

Message: 97 (0x0061).

Example: Read register 1 and 2 (Serial number 1 and Serial number 2) of

controller at address 5.

Sent: 05 03 00 01 00 02 94 4F

Received: 05 03 04 00 64 00 C8 FF BA

Message: 100 (0x0064) and 200 (0x00C8).

Write to a Single Register Command (0x06)

This command writes a parameter to a single register. The controller will echo

back the command. An attempt to write to a read-only parameter returns an

illegal data address error (0x02).

∆∆∆∆∆∆∆∆

controller address (one byte)

write to a register command (0x06)

data high byte

data low byte

CRC low byte

CRC high byte

Example: Set register 702 (High limit set point) to 200 (0x00C8) on controller at

address 9.

Sent: 09 06 02 BE 00 C8 E8 88

Received: 09 06 02 BE 00 C8 E8 88

Write to Multiple Registers Command (0x10)

This command actually writes a parameter to only a single register. An attempt

to write to a read-only parameter returns an illegal data address error (0x02).

NOTE: For more information about communicating with Watlow controllers, go to www.watlow.com and download the

Data Communications Reference: Electronic User’s Manual. It is located under Literature, User’s Manuals, English and

search on data communications reference.