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FCEUX and Mesen both have options to randomize RAM at power-on. I think Nintendulator does as well. I only found a setting for it in Mesen but it does not recreate the issue, so I'm guessing it only randomizes the RAM that's directly accessible to the CPU. Hey, maybe uninitialized RAM could be used...

Thanks for the replies guys, I'm learning a lot! I'm going to look into my initialization code again to see what I can improve. You guys wouldn't happen to know of an emulator with the ability to emulate the uninitialized behavior found in real chips? If so, that would be really helpful in debugging...

Hey, not sure where to post this but I thought it was a little interesting, so here it goes. I've just started experimenting with scrolling where I've added the ability to change scroll values while my game is paused. If I run the game in an emulator (fceux/mesen) and scroll to an area where I have ...

As a relatively new nesdever I'd recommend not worrying too much about tools in the beginning. You will gain a better understanding of how things are put together the longer you keep things basic. Following a simple tutorial with whatever tools used there will be enough to get you started. It's gonn...

What would one typically do to handle lag frames? Detect lag, flag it and avoid doing non critical stuff? I would simply have a variable that tells that the last frame was completed. It's set at the end of NMI and tested at the beginning of NMI. After the test it's cleared and things go on normally...

Konami games does "all in NMI" and handle lagging and re-entrant NMIs properly - by software (rather than disable further NMIs by $2000.7, it probably sets some flag or something so that further NMIs only do music and minimal work before returning to unfinished game logic buisness). That'...

I did this but the other way around, hooking up the ends of extension chords to my Sharp Twin Famicom inplace of the regular controllers. So instead of those short wired controllers sticking out the back I have regular NES extension chords. But why would you want to hook up an internal Famicom contr...

Maybe this video from Retro Game Mechanics could be of use? https://youtu.be/q15yNrJHOak If used to it's fullest by not changing the seed values outside of the routines, it apparently loops after 27776 calls. I implemented it in my game with some opcodes changed for the 6502 and it seems to work: ;;...

Thank you!

Hey guys and gals! Is there any way on the 6502 that you can check if all bits in the accumulator are set to 1 in a specific order in just one operation? I thought AND would do the trick but I can only check if ANY of the bits are set that way. This branches with AND: lda #%1000 and #%1100 bne :+ I ...

koitsu wrote:Hejsan svejsan!

Tjena mors!

Seems someone's gone and done it!

viewtopic.php?f=2&t=4020&start=30

https://www.romhacking.net/hacks/4180/

If you want the two player hack with Luigi's own sprite, this would be a bit more complicated: Since Mario and Luigi are on screen at once, you need both versions of their sprites on the screen, so you would have to use the different graphics banks not for switching between Mario and Luigi, but to ...

If I've understood correctly, this should be possible as long as both pointer variables (in this case some_pointer_lo and some_pointer_hi ) are on ZP and y never goes above 255? The former part of your sentence is correct: basically, ensure that some_pointer_lo is not ever $ff, otherwise this would...

Before the jsr , the 16-bit value in $0014/0015 is $20fe ($0014 = $fe, $0015 = $20) After the jsr , the 16-bit value in $0014/0015 is $2102 ($0014 = $02, $0015 = $21) If you want to know how this trick works, just ask. You might think the adc #0 serves no purpose, but it's incredibly important. Hin...