Timer immediately overflows when 0xff is loaded into it about jtopl HOT 5 CLOSED

Could you (@gyurco ) check if this new commit dfaa563 works ok with Wolf3d? I had to add that line to restore the music speed in Bad Dudes vs Dragon Ninja

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I did not try it yet, but doesn't this patch makes the timer run forever?

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BTW, I got an idea from a different implementation some time ago:

if (~din[7]) begin
  flagen_A   <= ~din[6];
  flagen_B   <= ~din[5];
  { load_B, load_A   } <= din[1:0];
end

E.g. bit 7 masks the update of REG_TIMER. It didn't make much difference with AdLib games, but maybe worth to try on arcades. Maybe Bad Dudes resets the IRQ frequently, and this should not stop the timers, as it does without the masking.

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I tried your patch, and it makes Adlib detection unreliable (the check code expects the timer is not triggering IRQ until its explicitly started).
E.g. after this sequence:

	alOut(4,0x60);	// Reset T1 & T2
	alOut(4,0x80);	// Reset IRQ
	status1 = readstat();

status1 must read 0 for both timer flags.

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No more issues encountered!

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