Dual Temperature Sensor

Note: This device is part of the XNET home network system. See the page on Home Networking for how to power and interface to this device. Any modifications, such as to rework it as a 'stand alone' device are up to you.

This device uses Murata thermistors (NTSA0XV103FE1B0) to measure 2 separate room temperatures in each module.

The curcuit consists of a PIC12F683 to read the thermistors and connect to the network. The 24k and 10k resistors on each themistor help to linearize the voltage - the rest is done in software.

The 2 modules are designated F1 and F2 on the network. Command available are are of the form


Command Function
T Report both temperatures
R Return raw data until key struck
V Return version number

This unit automatically generates temperature reports to the clock/console unit whenever either sensor changes. These are in the form...

/C1FnAdd (where n is the unit number, 'A' designates the first sensor 'B' the second sensor, and 'dd' shows the temperature)

Here are the Source and Object files along with the Layout.