MAMEDEV Forum

Hello,

I am starting to write the driver for a computer. It has a three 8255, one of which has a diagnostics port in its port B. Lectures on this port are done with a LED add-on that displays a the code of the last executed test. I have some skeleton of the driver, but I cannot find the library for the LEDs. I have looked into the IBM6580 Displaywriter as I know it uses them but I am still clueless.

Please, could anybody point me to the right direction?

Thank you in advance!

Hello again.

At the end I settled with 7-segment LED displays to show the diagnostics of the computer. However, the segments are driven directly, whereas I would be more interested in having an hex display. I imagine a conversion array/table may already exist somewhere around the code, so implementing it may be reinventing the wheel. Does anybody know where could I find such a piece of code?

Thank you in advance!

I have advanced a bit in the development of this system, however I am stuck. I do have lost the capability to add breakpoints when debugging, without them I am completely lost and cannot continue. I am sure it is the result of misconfiguration of the virtual machine, but I don't have enough experience to know where I am failing.

My code is at github.

Please, could you take a look at it?

Thank you in advance!