Engineering How to control stepper motor speed in emu8086?

[yukari1310]

how can we control stepper motor in emu8086?
we have to take input AT RUNTIME that if we enter 0 it will stop the stepper motor, 1 for slow speed, 2 for medium and 3 for fast speed.

 

[rcgldr]

What I/O port and how many pins are being used to drive the stepper motor? I recall doing this on an old PC in MSDOS, where it wasn't an issue to hook into the ticker interrupt and read the ticker count which ran at 1.19318 mhz (838 nano seconds per count) to get a very precise delay routine. 4 of the printer port pins were cycled through 4 phases to advance the stepper motor at various frequencies.

 

[yukari1310]

This question is actually intended for a treadmill development which include programming (speed change and incline functions) and memory interface. I have hard time understanding a coding let alone writing one. Do we assign the meaning of I/O port ourselves?

 

[rcgldr]

Do we assign the meaning of I/O port ourselves?

Yes, but emu8086 is an emulator, not a piece of hardware. Some type of hardware controller is needed, and the I/O ports will need to be specified. The I/O port pinouts will have to go to yet another controller that converts the pinout signals into the voltage and current required to drive the treadmill motors and also the displays. Other stuff like a power supply and sensors (to prevent excessive movment of the incline) would also be needed.

 

[yukari1310]

I found out that I do not need to control a real motor but write a coding that will give voltage at the output port instead. I am to build an interfacing circuit. How do I connect LEDs (output port) to it? And where/how should I accept the input?