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Kale Offline OP
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Native normal resolution here is 640 x 200, and it's quite a normal resolution actually (for instance PC CGA was 320 x 200 or 640 x 200). Snaps looks ugly simply because MAME / MESS snapshots doesn't take the pixel aspect ratio when it's the time to save into PNGs (and I'm lazy so don't want to hand modify them).

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Kale Offline OP
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Fixed a silly bug with CRTC disabling, fixes text garbage with various games:

1942





Alphos:





A.I.R.:




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Kale Offline OP
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Layer masking actually applies only on b/w mode, that was rather obvious with Bug Attack (that was setting 0x0e on the register) ...




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Kale Offline OP
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Made the TC timer to go low on a longer time. I don't yet know how that truly works (i.e. if I have to check anything inside the upd765 emulation for this), but this fixes Aploon booting for now.





EDIT: actually, it fixes a "somehow" better game wink




Last edited by Kale; 01/21/11 06:24 PM.
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Very nice. Is that last game one of the Y's?

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Kale Offline OP
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Yes, it is.
Added irq latch mechanism, this makes all three Ys to work on this machine smile (minus hanging sound, caused by the lack of proper i8214 emulation hook-up / another bug with irqs)




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Kale Offline OP
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Added N-BASIC GFX mode attribute, used by some games like Bu U Ma or Kuronekosou Souzoku Satsujin Jiken title screens:





In this mode, tilemap cells are divided into 4 x 2 strips, on which bit 0 is top-left, bit 4 is top-right, bit 3 is bottom-left and bit 7 is bottom-right

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Kale Offline OP
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First step in emulating the CD-ROM interface on PC-8801MC variant ... hacking it to boot instead of the Basic BIOS and I've got this ...

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Kale Offline OP
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Here's the corner of busted code snippets, Cuby Panic by Game Arts does this:

21FD: ld ($EC41),hl
2200: ld a,$02
2202: ld ($EABD),a
2205: ret
9107: di
9108: ld a,($E6C2)
910B: set 1,a
910D: out ($31),a
910F: ld ($E6C2),a
9112: ld hl,($A808)
9115: ld ($A808),sp
9119: ld sp,hl
911A: ei
911B: ld a,$47 ;from here onward it stamps copy protection message
911D: call $A59E


I don't know what it's supposed to do, but if you change 0x911b to a ret then game works fine ... also, one of the floppy images doesn't have this check at all.


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It looks like it is expecting an interrupt to already be waiting or about to fire when it executes the EI at 911A, which would fire either right before or after the ld a,$47 at 911B

LN


"When life gives you zombies... *CHA-CHIK!* ...you make zombie-ade!"
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