"...O frabjous day! Callooh! Callay!' He chortled in his joy."
Today I finished porting the code to the Olimex Duinomite Mini board, so now you can have your emulator for about $25 USD (for what we paid upwards of a couple grand in the day), and soooo much more reliable. (and no soldering for the Olimex board).
I have tested video, keyboard, SD card (cassette/floppy), and sound. I believe the porting task to be complete.
I have updated the project-related file to now contain both firmware images, one for the UBW32 (based) board, and also the aforementioned Olimex board.
The Olimex board does imply some limitations:
- it is a monochrome only VGA board. Since the original TRS-80 was monochrome, this isn't the end of the world, but you won't be able to simulate the green screen filter. Also, pay a little closer attention to the controls states in the 'hypervisor' since you won't have color cues to guide you. But I think the reverse video does an adequate job of letting you know what control has the focus.
- this board does not have a battery-backed RTC, alas. I haven't really been using that feature yet, anyway, since OSs needed to be patched to use the aftermarket RTC's of those days. I guess it would affect the file modification date on the SD card, but who cares?
- this board only has one PWM channel, so you won't get Orchestra-85 stereo. I arbitrarily selected 'right' as the available channel. The cassette-based sound is directed there, so you can play all the games just fine. Do note that the PWM channel on this board is not capacitively coupled.
- this board can be run from USB power, or from adapter by selecting a jumper near the jack. YOU MUST USE ONLY 5V REGULATED ADAPTER with the Olimex board. Not even 7v. Get a cheap 5V switcher wall wart off ebay or something. There is a zener on the board to help a little with booboos, but mr zener gets pretty hot and cranky when he's made to work.
I guess what I have left is serial emulation, maybe hard disk, maybe some sort of printer, and maybe a 3D printed case might be nifty.
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