NESpire general discussion thread

[annoyingcalc]

can you make sonic work for me it gives a blank screen

[Yeong]

...oh. my bad.

[Reo]

I'm unable to compile this with a "stock" build environment. I'm getting all kinds of abnormal errors from the assembler as if something's not set up right, and yet, I'm able to compile the "hella" example as well as C++ examples with no problems. Any kind of obvious solution?
EDIT: Because "abnormal errors" was too vague:

[Goplat]

can you make sonic work for me it gives a blank screen

Sonic has anti-emulator protection (or possibly just bad programming), which is not so easy to fix. It's getting stuck in the following loop:

E4DC   AD 02 20   LDA $2002
E4DF   10 FB      BPL $E4DC

This loop waits for the high bit of address $2002 to become set. The NES sets this bit at the beginning of the vertical blanking interval of each video frame. However, the NES *also* invokes an interrupt handler at the same time, and this game's interrupt handler takes so long that by the time it returns, the vertical blanking interval is already over, so $2002's high bit is clear again - the loop can never exit. The only reason it works on real NES hardware is because eventually the vertical blanking interval will happen to start in the middle of reading the LDA instruction, so the instruction reads a value with the high bit as set, because the interrupt won't be called until the instruction is finished. I can't emulate things happening in the middle of instructions; having to check for that would be extremely slow.

It seems to work if you just patch out that offending routine - hex-edit a copy of the ROM and change the byte at 3E4EC from AD to 60 (a return instruction).

Reo: Those errors imply you're trying to use an x86 assembler, rather than the ARM assembler required.

[Reo]

But I'm using your makefile, so it should be calling arm-none-eabi-gcc.
EDIT: I changed "%.o : %.S" to "%.o : %.s", and it's working better. However, it's still saying...

Code: [Select]

main.s: Assembler messages:
main.s:75: Error: ARM register expected -- `mov cpu_a,#0'
main.s:76: Error: ARM register expected -- `mov cpu_x,#0'
main.s:77: Error: ARM register expected -- `mov cpu_y,#0'
main.s:78: Error: ARM register expected -- `mov cpu_sp,#0x100'
main.s:79: Error: ARM register expected -- `mov cpu_flags,#0'
make: *** [main.o] Error 1

...which makes me think it's not including nes.inc. Still, I don't have much to solve at this point. (I think)

[Goplat]

But I'm using your makefile, so it should be calling arm-none-eabi-gcc.
EDIT: I changed "%.o : %.S" to "%.o : %.s", and it's working better. However, it's still saying...

It has to be a capital S; gcc won't use the preprocessor if the input file is named with a lowercase s.

...and I just realized I screwed up and named the files with a lowercase s anyway, which doesn't matter on Windows (case insensitive) but would be a problem on Unix (case sensitive). If you're using a Unix-like OS, just rename the files to have a capital S and it should fix it.

[Reo]

Aha, that worked! I'm using MinGW, so the case-sensitivity was the problem.

The reason I'm trying to build it is because I wanted a build with the controls being both on the right side and closer together. I'll attach my changes + source to this post. I've tested it with Super Mario Bros, but I doubt what I changed broke anything.

[JasonCheeseballs]

Uh I need help. I have the t-nspire cx cas ( colour screen) and I can't get nespire v0.30 working.

Ok so I have nespire v. 0.30 and SuperMarioWorld.nes.tns

I'm inside the emulator and it displays SuperMarioWorld.nes.tns

I press shift to start and nothing happens....

it then says ERROR: unimplemented mapper

What do I do? I've spent hours trying to find the answer but can't find it.

[Lionel Debroux]

Looks like NESpire is signaling you that the game uses something it doesn't know how to emulate. In that case, all you can do is wait for it to be implemented some day (if possible)

[calc84maniac]

Plus, Super Mario World is not a NES game. (Unless you're using some sort of rom hack of a NES game, but in that case it probably sucks anyway)

[AzNg0d1030]

Plus, Super Mario World is not a NES game. (Unless you're using some sort of rom hack of a NES game, but in that case it probably sucks anyway)

Unless he meant Super Mario Bros.

[ralphdspam]

Plus, Super Mario World is not a NES game. (Unless you're using some sort of rom hack of a NES game, but in that case it probably sucks anyway)

Unless he meant Super Mario Bros.

There is a Mario World clone for the NES.  It's not great, but it does exist. 

[JasonCheeseballs]

I have street fighter III and starwars which are .nes.tns and those give the same error message. Plus if goplat released v0.30 isn't it supposed to work? I'm pretty sure it should just work with the colour calc.

*edit* Uh Well so far only I managed to get super mario bros 3 working so that means the other roms were fake or unrecognized.

[TIfanx1999]

Hey, welcome here Please use the modify button if you have something to add. Double posting is not allowed unless 24 hours have passed or you are posting a project update. I combined your two posts.

[Goplat]

ERROR: unimplemented mapper

Guess I had better explain this. The NES hardware only provided 32kB of memory space for program ROM and 8kB for character ROM. This wasn't enough for most games, so to overcome these limits they would add hardware in the cartridge, called a "mapper", that the game could use to map different parts of ROM (and sometimes RAM) into memory. Some mappers would have other functions as well.

There are over 100 different kinds of mappers that have been used, and some are very complicated, so being able to emulate every one of them is a tall order. I've implemented only a few of the most common ones.