Denial

You could try detecting reads from uninitialised memory, and depending on the memory location that the read is coming from and going to put the most likely value to work in.
That'll be my initial fix, hopefully I can get a combination that fits all the buggy games.

I've spent about 20 hours on games that don't seem to work right in my emulator, and most of the problems have come down to one thing. Games using unitialised memory. Poker and AE are two examples. In AE PAL at least, the screen is sometimes offset to the left and up incorrectly all due the intialis...

I'd love to, but shipping at aus$100 within australia plus 25% extra for exchange rate plus shipping to NZ sounds painful.
I'm thinking like $600+

http://cgi.ebay.com.au/ws/eBayISAPI.dll ... K:MEWAX:IT

Must stop looking at it, or I might do something rash

Saved another cycle and removed the zero page self modifying code! 2 tya ; this does (y&~7)*3 i.e. (y>>3)*24 3 and #~7 ; (y&~7) 3 sta $temp ; $temp = (y&~7) 5 rra $temp ; a = (y&~7) + (y&~7)>>1 = (y&~7)*1.5 2 asl ; A<<1, A holds low result now, carry holds high bit 3 sta WORK...

ok King Tut code sucks... I was trying to load the csm of it, that failed, then I tried the tap and that failed the same way. I loaded up vice and added a break point, and it turns out there's some dodgy code in king tuts start routine. ISB $5554 <- undocumented instruction NOOP $0F,X <- same. what ...

1/ It's fun 2/ I prefer c++ 3/ A completely different UI to vice, with emphasis on helping developers to develop. 4/ An emphasis on exact emulation, it should do exactly what the vic20 does, down to the screen corruption when you scroll the vic too far right, or unconnected ram reads, or preventing ...

I believe it's an unexpanded game.
If I skip that loader and just load normally it seems to work.
I think there's something wrong with my tape load routines, as if i type the program in by hand it works fine, but if i load it and run, it does that bad branch.

Thanks for the help.

I'm trying to load King Tut from tape, and it keeps failing with the following (below). The question is what's the JMP ($0014) meant to do. And, given the program below, why is line 18 poking stuff to the keyboard buffer and what's the inverted "E". DCB8 STY $68 DCBA RTS D804 LDA $64 D806 ...

I was just thinking we could just rewrite the kernel/basic roms.
If we worked out the memory locations of all the procedures with inputs and outputs then got many people just to write one function, it could be done in no time.

At some point I'd like to release my Vic 20 emulator, but I'm a little worried about the issues surrounding copyright on the kernel/basic roms, also 1541 drive roms. As I'd like to add a donation option to the emulator, I don't wan't whoever owns the copyrights to lawyer up and make my life a pain. ...

Yup it was intended for zeropage, i've modified the note comment.
If you were putting it somewhere else, you'd add the extra cycle and use a temp zp location.

Is it possible to use a 24 wide screen? Then you could save a fair bit of code and time. Note: Code needs to live in zeropage, and not tested yet. ; (WORK),y points to SCREEN+(y>>3)*24 2 tya ; this does (y&~7)*3 i.e. (y>>3)*24 2 lsr ; y>>1 3 and #~3 ; (y>>1)&~3 = (y&~7)>>1 3 sta $self_mo...

http://sleepingelephant.com/ipw-web/bul ... ght=svideo

also in Wiki

http://sleepingelephant.com/denial/wiki ... deo_output

To figure it out I executed this program, that basicially inverts and un inverts the screen the moment it detects a scanline change. With the 3 x NOPs I have in the code the disruption on screen occurs at minimum exactly on the default left hand edge of visible screen (i.e. on the left of the first ...