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ca65 overrides address size using z:, a:, and f: prefixes for direct, absolute, and absolute long respectively.

In addition to the .dpage, I guess you'd need a default data bank register for instructions that use absolute addressing mode.

Great to see 65816 finally coming to asm6!

Even if you can track DP, I think a directive for manually setting DP is good to have. That way, adding HuC6280 support would be easy too I guess.

TAD is an alternate of the official TCD mnemonic I think. I guess the official mnemonics are supported too?

Yeah, that would be a good addition...I'm thinking ending the opcodes with ".b",".w" or ".l"? ca65's way might be easier, just depends on how the colon would be handled by asm16.


Your preferred functionality is what the assembler does currently, since it doesn't really know what direct page is (it just guesses that everything below 0x100 is "zero page"). Why not let the assembler guess if the user wants direct page, though?


I always do that with lda #bla & $ffff. $ff to set to 8-bit.


You mean to use on long addresses?


Oh yeah, I wouldn't implement automatic DP if there wasn't a manual alternative.


Yep, all official opcodes and aliases should be supported.

With PRG bank set to $7E and direct page set to $2100, what should LDA $7E2100 do? Doing LDA $7E2100 & $FFFF would change it to $2100, which automatically gets recognized as zero page.


Yes.

That's a tricky situation. And just when I pushed the commit on my computer, too... Maybe automatic direct page shouldn't be a thing.

If I do end up putting it in anyway (probably not at this point) then the data bank will be handled by the assembler too. asm16 would solve the $7e2000 program fine if you put in the entire value. Using & $ffff makes it clueless.