Keyboard input drops keystrokes on Atari 800

[rubeon]

Hi,

when typing with a USB-attached keyboard, keystrokes are not reliably registered when typing quickly.

Keyboards tried:

• Apple extended keyboard (aluminium)
• Unicomp USB keyboard

To reproduce:

• boot into Atari Basic
• type a few sentences at reasonably quick (but normal) speed

Expected Results

• "the quick brown fox jumped over the lazy dog"

Actual Results

• "te quck brn fx jumpd ovr te lzy dog"

I believe this is caused by overlapping keypress/keyup events when typing quickly. The keyup on "t" could overlap the keydown on "h" for example.

When two-finger typing, this occurs much less often.

FYI this behaviour does not occur on the Atari800MacX emulator, they may have some kind of event queueing in there.

I never had a real Atari 8-bit, so I'm not sure if this mimics the real hardware's behaviour.

[sorgelig]

Old computers may not suited for quick typing. I don't think there is a problem with HPS side of keyboard handling, so it must be inside the core, and more particular - inside the Atari software. Probably some workaround can be added to use FIFO and feed to Atary keyboard matrix at slower pace.
This should be done by Atari 800 experienced developer who understand the firmware of A800 and how it can be tricked.

[norrinr]

I personally feel the same issues typing quickly on real hardware (600XL, 800XL, 130XE) that I feel in this MiSTer core.