This is a small program to output the voltages and temperatures from the PC87366 chip in the Net4801 computer from Soekris.com
The program is for FreeBSD-Current but can readily be adapted to other operating systems by changing the opening of /dev/io to whatever magic is necessary.
ComBios rev 1.22 or later is needed.
First run the program with a "-i" to initialize the hardware:
# ./env4801 -i
Then, as often as you feel like, read out the measured values:
# ./env4801 VREF = 1.214 V245 = 2.450 Temp 2 (status=0x81) 54 C Volt 1 VCORE 171 1.987 V scale 1.0 1.987 V +/- 0.0116 V Volt 2 VCC 212 2.463 V scale 2.0 4.926 V +/- 0.0232 V Volt 3 VPWR 56 0.651 V scale 20.1 13.078 V +/- 0.2335 V Volt 4 +12V 211 2.451 V scale 4.8 11.841 V +/- 0.0561 V Volt 5 -12V 213 2.475 V scale 19.2 -11.264 V +/- 0.2230 V Volt 6 GND 0 0.000 V scale 1.0 0.000 V +/- 0.0116 V Volt 7 Vsb 141 1.638 V scale 2.0 3.276 V +/- 0.0232 V Volt 8 Vdd 141 1.638 V scale 2.0 3.276 V +/- 0.0232 V Volt 9 Vbat 255 2.963 V scale 1.0 2.963 V +/- 0.0116 V Volt 10 AVdd 139 1.615 V scale 2.0 3.230 V +/- 0.0232 V
The scale value is the ratio of the resistor network.
The numbers are generally within 3 percent (5 % for -12V). Precision can be improved by measuring the VREF voltage over the capacitor marked in the picture below and specifying the correct VREF with the "-r" option.
