Owner manual
Custom Projector Enclosure
8/15/2005
Temperature Controller with
Active AC and Heater
RS232 Interface
Hardware
Standard three pin hookup, 2,3,5, on DB9. Baud rate 9600,N,8,1. No handshaking.
Software
ASCII letters followed by a delimiter, carriage return (ASCII 13).
Commands from Host to Controller:
Command Description Example
Q Request Current Temperature
Q↵
Axxx Set Level that AC turns on/off at
(will turn on if temp above this level)
A080↵
Bxxx Set Level that Heater turns on/off at
(will turn on if temp below this level)
B050↵
Cxxx Set Alarm Level (alarm on if hotter than this level)
C110↵
Dxxx Set Power Cutoff Level (cutoff if above this level)
D120↵
xxx-temperature ↵ Carriage Return (13)
Communications from Controller to Host:
Command Description Example
Txxx Current Temperature
T073↵
G AC On
G↵
H Heater On
H↵
I Alarm On
I↵
J Power has been switched off
J↵
S (O,C) Door Switch is Open/Closed
SO↵
SC↵
M Motion Sensor Tripped
M↵
K Received Set command, Executed OK
K↵
X Can not understand Command
X↵
xxx-temperature ↵ Carriage Return (13)
Notes: All temperatures are in Fahrenheit. Host program to convert to Celsius if required. G,H,I,J are
sent every few seconds when those levels have been tripped. S is sent upon change of state. M is sent
upon shock sensor being tripped. Temperatures range is from 1 to 250. Temperature and settings are
in two degree increments. On reporting only, if current temp is negative, then response will be T-015.
Do not set Axxx equal or below Bxxx !
Heater will turn off when door is open.









