I'm slightly surprised that no one has suggested PDP-11 assembler as a good starting point if you're not going to learn a current instruction set. Perhaps it's because it was the first one I learnt properly but all the early miccroprocessors felt like a step backwards. I did spend a few years writing Z80 assembler but I wouldn't recommend it nowadays as it's not a very orthogonal instruction set and 6502 doesn't have enough registers to give you a proper feel for writing assembler.
I believe 6502 instruction set is a good first assembly language
91–100 of 297 posts
Re: I believe 6502 instruction set is a good first assembly language
#92The topic of the 6502 ISA simplicity is a pet peeve of mine, because to me it's clear that anybody thinking that such simplicity is a good thing, never progressed past a hello world.
Programming anything of moderate complexity on the 6502 is hard. 8 bits are way too restrictive (e.g. screen addressing on the Commodore 64). Multiplications/divisions need to be hand-rolled. And even 16 bit sums/subtractions are simple but still not trivial to perform efficiently.
The 8086+DOS platform is way easier to work on, in comparison (if one wants to learn basic assembly).
Re: I believe 6502 instruction set is a good first assembly language
#93Earlier quoted context omitted.
> real available hardware Last I checked the 65C02 was still being manufactured and sold. It can also at a blazing 14 MHz.
It's $8 and can't run without external ROM and RAM and a clock circuit and some glue logic. A RISC-V CH32V003 32 bit processor with 2k RAM and 16k of flash running at 48 MHz costs $0.10 for an 8 pin package (6 available I/O pins) or $0.20 for the 20 pin package. Once programmed, it needs only electricity between 2.8V and 5.5V to be applied to start running. https://www.aliexpress.com/item/1005005036714708.html You ca…
> It's $8 and can't run without external ROM and RAM and a clock circuit and some glue logic.
True but I've always found that there was a special 'charm' to these old CPUs because you have to build the circuit you described as a bare minimum, which is not difficult and makes you learn a range of skills.
Re: I believe 6502 instruction set is a good first assembly language
#94What about the 6809 processor? I believe this was even simpler, it was very consistent.
Re: I believe 6502 instruction set is a good first assembly language
#95I cannot agree that the simplicity of the 6502 wins over the 68000. The 68000 has more registers and wider data types: but the registers are all uniformly the same. It's really just two registers A and D, copied a bunch of times in to D0 to D7, and A0 to A7. Whatever you can do with D0 can be done with D3 and so on. Some A's are dedicated, like for a stack pointer. Simplicity of structure has to be balanced with simp…
> The best way to learn how to hack around the limitations of a tiny machine is to completely ignore them and become a seasoned software engineer Learning to hack around the limitations of a tiny machine is a good step toward becoming a seasoned software (and possibly hardware) engineer! The advantage of tiny systems is that you can understand them completely, from silicon to OS to software. The 6809 is simpler than…
Totally! I wrote an assembler once for the 6809, it was a lovely architecture.
Re: I believe 6502 instruction set is a good first assembly language
#96> the “S” in RISC stands for “simple” TIL
Quick, we need to come up with a retconed acronym(retronym) of RISC that makes the "S" into simple.
Re: I believe 6502 instruction set is a good first assembly language
#976502 was my first assembly, though we didn't have an assembler - we entered raw opcodes into the Epyx FastLoad monitor on the C64. You kids with your symbol tables and your fancy mnemonics. a9 01 8d 20 d0 a9 93 20 d2 ff ... When we got a KIM-1, we were able to write meaningful programs on it in a weekend, since we already had memorized all the hex.
White border with a cleared screen looks good.
Re: I believe 6502 instruction set is a good first assembly language
#98The accumulator A is your mouth with 8 teeth, that can bite and chew and taste, the status register is your tongue, and the X and Y registers are your hands, that can help you shove stuff into your mouth and spit it out.
Re: I believe 6502 instruction set is a good first assembly language
#99I cannot agree that the simplicity of the 6502 wins over the 68000. The 68000 has more registers and wider data types: but the registers are all uniformly the same. It's really just two registers A and D, copied a bunch of times in to D0 to D7, and A0 to A7. Whatever you can do with D0 can be done with D3 and so on. Some A's are dedicated, like for a stack pointer. Simplicity of structure has to be balanced with simp…
> The best way to learn how to hack around the limitations of a tiny machine is to completely ignore them and become a seasoned software engineer Learning to hack around the limitations of a tiny machine is a good step toward becoming a seasoned software (and possibly hardware) engineer! The advantage of tiny systems is that you can understand them completely, from silicon to OS to software. The 6809 is simpler than…
The 6809 is the Chrysler Cordoba of 8 bit microprocessors, the personal sized luxury processor with styling in timeless good taste, rich Corinthian leather, and an efficient sophisticated multiply instruction.
Re: I believe 6502 instruction set is a good first assembly language
#100The best beginner assembly hands down is Z80. It may be a bit harder to start with, but if I could write games in it at 14 years old, an adult should have no issue at all.