NesASM 3.01 addressing and syntax errors

[Petruza]

I've got NesASM 3.01 from here: http://www.nespowerpak.com/nesasm/
Not the .exe since I use MacOS, but built the sources.

I'm coding a simple CPU test, and get this errors:

Code: Select all

   67  00:C02B                    STX $0,Y
       Incorrect addressing mode!

  105  00:C056                    STA ($0,X)
       Syntax error in expression!

Isn't STX ##, Y a valid instruction and addressing mode? ( opcode $96 )

And what's the syntax error in STA($0,X) ?

[tokumaru]

And what's the syntax error in STA($0,X) ?

Doesn't NESASM use '[' and ']' for indirection?

[tokumaru]

Isn't STX ##, Y a valid instruction and addressing mode? ( opcode $96 )

Just remembered: I think NESASM doesn't use ZP addressing by default (since STX ####, Y doesn't exist you get an error), you have to use '<' before the address to indicate that you want it treated that way.

[Petruza]

Ooops!
Neither the docs nor the example codes had any indirection example, so I guessed ()
Gonna try, thanks!

[tomaitheous]

Does NESASM have the bug where if a single instruction crosses over an 8k region it will error out on a bank overflow?

[Memblers]

Does NESASM have the bug where if a single instruction crosses over an 8k region it will error out on a bank overflow?

Yes, but I'm not sure about v3.01. It's a really annoying feature, since almost no one uses 8kB banks.

[tepples]

[Enforcement of 8192 byte ROM areas is] a really annoying feature, since almost no one uses 8kB banks.

Yet. This will change if bunnyboy ever finishes his MMC3 on a CPLD. In fact, when I first read about NESASM's 8 KiB bank model, I thought it was because of the MMC3, not because of the assembler's PC Engine heritage.

[tomaitheous]

[Enforcement of 8192 byte ROM areas is] a really annoying feature, since almost no one uses 8kB banks.

Yet. This will change if bunnyboy ever finishes his MMC3 on a CPLD. In fact, when I first read about NESASM's 8 KiB bank model, I thought it was because of the MMC3, not because of the assembler's PC Engine heritage.

I always thought PCEAS was a modified version of NESASM, not the other way around. Though... NESASM appears to use Hudson's NES/FC 6502 assembler syntax.