TE Technology TC-24-25 - Manual (Page 25)

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checksum from the query were not correct the temperature controller would send back:
(stx)XXXXXXXXc0(ack).
III. RS485 or RS232 Communications Parameters
A. Baud Rate 9600
B. No Parity
C. 1 Start Bit 1 Stop Bit
NOTE if you are using communications software different from the one supplied with the
controller: The demands of temperature control require a relatively large portion of the
processing power of the onboard microcontroller. It is possible for a host computer to send data
too quickly for the controller to receive and update. TE Technology recommends adding a delay
between each character sent to allow the controller sufficient time to process the information. One
millisecond might be a good delay time to use initially, but the exact time will vary depending on
the host computer’s hardware and the particular demands on the controller at the moment.
IV. Commands
1. INPUT1 (controlled input value)
Write Command: NA
Read Command: 01 hex
Interpret: Divide returned fixed-point temperature value by 10.0 and convert
to degrees F/C decimal value.
Example:
Receive 100.0 °F temp from unit (sensor type = 1).
Send: *01010000000042(etx)
Receive *000003e8c0^
Convert hex 000003e8 returned to decimal = (1000)
Divide by 10.0 = (100.0°F)
2. DESIRED CONTROL VALUE (set value)
Write Command: NA
Read Command: 03 hex
Interpret: This command returns the set value determined by Input2 or as a
fixed value set by communications (see #1 above for interpretation).
3. POWER OUTPUT
Write Command: NA
Read Command: 04 hex
Interpret: -255 represents –100% output.
0 returned is 0% output.
255 represent 100% output.
4. ALARM STATUS
Write Command: NA
Read Command: 05 hex
Interpret: 0 returned means no alarms.
Bit 0 = 1 means HIGH ALARM.