Well, I have written a lot of code on 6502.

What you name is the value to be operated on, and that is indexed, zpage, immediate, etc... the accumulator is not named. There are two or three bytes, one instruction, one or two for value or address.

Same for things like ADC, the accumulator is where it will happen, the things you name are values and addresses.

LSL, LSR can just be stated, one byte instructions that operate on the accumulator, which does not need to be specified.

6502 is really basic. The accumulator is the working register for many things. The index registers are for indexing. One does not do LDX $c000, A for example.

I believe you. But it was, quite typically, like you can see in the Woz code above. Or from '6502 Assembly Language Subroutines', 1982 vintage.

http://i.imgur.com/jreIWA5.png

Yeah, it can be. No worries. Guess I never assembled on something that required it.

Fun old times in any case. That chip provided just enough, and no more.

Memory operand is not a register operand. Unless you're one of those who consider 6502 zero page as 254 registers (IIRC, you couldn't use addresses 0 and 1, at least on C64, because they were used for ROM visibility and I/O control).

The C64 used the 6510, not the 6502. The zero page definitely has 256 bytes in it normally!

Ok, 6510. Regardless I was talking about C64. You can't safely use addresses 0 or 1, because they're memory mapped I/O.