I'm tasked to use a DB25 parallel port to take in a digital 8-bit result from an ADC and process it into a signal which can be displayed by Seven Segment Displays using emu8086. I'm also needed to use User Port to access the real parallel port. After taking in digital 8-bit from ADC, the process will be continued using emu8086, then outputs to a decoder then to the Seven Segment Displays.
I've tried plugging the parallel port into my desktop, which then connects to a circuit of simple LEDs and resistors. At the moment I connected them, all 8 LEDs lit up. Why is it so?
It seemed I can't control the circuit hardware just by using User Port and emu8086 through a parallel port.
I've looked up some sites saying that in order to connect the real parallel port to the virtual port of emu8086, I'm required to involve C++. I had some C++ basics with me, but I can't figure a way or codes to connect the parallel port to my emu8086, I've searched a few sites but I don't understand the purpose of the codes.
Can anyone kindly show me some sample codes on how to connect my User Port and emu8086 using C++?
Thank you.