A PC controlled 4 channel temperature meter (either deg C or F) using the serial port, a PIC12C509 and 4 x DS1820. No external power required. We think that each DS1820 may be located over 200 meters away from the motherboard and PC. This is an ideal use for old 386 and 486 computers: continuous temperature data logging. Users will have to massage the input data stream to their purpose. It may be dumped into an Excel spreadsheet, or they can write BASIC programs using the INPUT command to grab the readings. As you can see from the photo there is not much to the hardware. 1. You can use term.exe our no-frills terminal program to see the data on the screen. Just run 'term 2400' (and you may have to press Esc to start the display.) The raw temperature data will display on the screen. 2. Or you can use some software the developer of the KIThas written. Tested on MS-DOS 4.00.950 on a 386/25 using floppy disk only, and on a machine with a hard drive. With floppy disk, do not exceed a logging rate of once every two seconds. Unpack the ZIP file onto a bootable floppy or a hard disk directory, then run TSL.EXE. If you have no hard disk partition, ignore the warning message about "c:\cwsdpmi.swp".