This is a PC Printer Port ADC.

Yes another but it is 10bit, and 11 Channel.
The hard work is done by the ADC itself the MC145050.
It has all the multiplexors, sample and hold, ADC, serial control on one chip.
The only other real bit is done by the REF25Z, thats a 2.5V reference for the ADC.
Its all powered from a couple of data lines driven HIGH.

The file here are:
readme.txt      This file.
parts_list.txt       The very short parts list.
adc11scm.gif    The circuit diagram in GIF format.
adc11pcb.gif    A suggested PCB layout in GIF format.
adc11.bas(.txt)       A Qbasic driver program.
adc11.c         A little turbo C program.
pclpt1.txt      A quick explaination of the PC's LPT1 as used here.
constrct.txt    A short tutorial in how to build it.
pinout.txt      The ADCs pinout.
lptcon.txt      The lpt port's pinout for the DB25 connector.

MFL'95