Remote Temperature Sensor (RTS)

The purpose of this application is to measure temperature using the 8-pin PICmicro™ and SMT 160-30 temperature
sensors. The temperature range is -45°C to+127°C.
The Remote Temperature Sensor is part of a
system that can monitor the temperature in 8 different
points. Each RTS has its own address (0 to 7) and communicates
with the master by a simple protocol.
Because of the low consumption of the RTS it is powered
from the data line (something like Dallas bus). For
communication is used 9 bit Asynchronous serial protocol
with baud rate 9600. The 9-th bit indicates that the
byte is address.
The protocol is: Master sends address.
The RTS which address matches sends data
Master sends address every 100 ms. The time between
communications is used by the powering capacitor to
charge up, so in this time the line must be in 1.
The slave monitors the line and when it finds start bit
starts receiving. If the address matches, a function
MakeTemp is called. This function measures the temperature and places the result in ByteOut Next Byte- Out is sent out and the 9th bit is sent as 0 (Byte is Data).