The project has ability to measure temperature from up at 8 DS1820 digital temperature sensors all on the same one-wire bus and Log it to a PC using RS232. It can be used to measure temperature at range -55 to +125°C without calibration. This AVR AT90S2313-based project use only 3 wires for all the temperature sensors: GND, VCC and 1-wire data. All sensors will connect to the same cable.
“With this unit the microcontroller will search the bus automatically for all present DS1820’s and record thier serial numbers in memory. You just connect the sensors and go. You dont have to program in serial numbers of each device”, said Wayne Peacock, the project designer.
Other features including high 0.02°C resolution readouts, displays up to 2 temperatures on the LCD panel, DS1302 real time clock with over 3 months backup, and supports Wayne’s NTP format for updating the clock to a time server.
Multi Temperature Sensor
Project Firmware, Schematic and Documentation