This OS allows you to use the parallel port for a lot of electronics test equipment from a CD,DVD or floppy disk. This OS works with most 32-bit computers although it can run on 64-bit. It contains a lot of scripts that can be used for interfacing.
Features:
555 Resistance Capacitance meter(rcmeter command)
logic probe(LProbe command)
square wave generator(square command)
digital to analog convertor(VOut Command)
Sine wave generator(sine Command)
Sawtooth generator(saw Command)
help file written in Windows Write program(help command).
runs Windows 3.1 apps
You can find the floppy image installer(Setup32.exe), source code, schematics in the ISO file.
NOTE: RCMETER may never return on too small capacitors or small resistors. To get a negative voltage on your waveform just put a 100 nanofarad capacitor in series with the Resistor Ladder Output, but be aware that DC voltages will be blocked if you use a capacitor.
Working 64-bit computers
- Dell Optiplex 330
DIgital To Analog converter 
Full Speed Sawtooth 
Full Speed Sine Wave 
Opamp Buffer for more current output on DAC
Click here to buy the cord I used. Click here to see the pinout(it shows you what color of wire from that cord goes where)
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