Hello

I am currently looking for some resource that would show how the internal control logic works on 6502 on the hardware level.
I am interested in by-cycle breakdown, (ex. what control lines are actuated on each stage of the instruction, what happens on clock transition high and low <- this is ...

Some (many? most?) assemblers do that with the "<". So for example, for the C32 assembler I use, if I'm programming for the 65816 and have the index registers in 8-bit mode and want an 8-bit LDX immediate, I might say LDX #<$1F, because without the "<", it would lay down a 16-bit operand.

Hm ...

I used that as an example, i meant any expression in brackets in general.
Using other brackets for me would be problematic though, as my current syntax uses {} to explicitly specify bit width of a value.

I have a list of requests for assembler writers at http://wilsonminesco.com/AssyDefense/assemblerRequests.html .
Thanks, I'll check it out!
Also, what do you think is the better way to treat indirect addressing syntax?

I currently do not allow bracketed expressions as the operand for indirect ...

as65 defaults to needing :'s but there is a flag to make them optional, so it can assemble source designed for a different assembler. (Also see "Postel's Law")

Hm, yeah i probably should have a similar option.


As for directives - conditional assembly and include another file along with the ...

Hello

I am currently in the process of making an assembler for the 6502 family and i do have a working in-dev version of it (only 6502 and 65C02 w/o Rockwell as of now tho).
And i am thinking of what syntax to support with it. For example some assemblers use ':' for labels whereas others dont ...

I want to make a python script that would generate C code for a project i am working on because i dont want to fill all 6502 instructions by hand (not only instructions but also the opcodes, operand count, byte size, etc.) and i need a convenient instruction set table i can usse to feed the script ...

Hello

I have been making an emulator for 6502 for the past week but i am stuck at an issue.
WARNING: this question is not entirely about 6502, but more about emulator design in general.

The CPU emulation code can currently run at ~70-80MHz on average, but i am having trouble controlling the ...

Hello,

I have been wondering if there was a 32bit evolution of 65816, would it stay accumulator oriented (have 1 32bit accumulator that can be subdivided into smaller ones like 816 for example) or would it have multiple full sized general purpose registers (for example 2 accumulators)?

What are ...

Hello

I have been wondering, what hidden registers does 6502 have if any?
By hidden registers i mean registers that are not available to the programmer at all, cant be directly modified or read by any instructions and are only used for internal CPU operations.
For example in a hypothetical CPU a ...

Hello

I have been confused for some time regarding patents and all the legal stuff about 65xx family so decided to ask.

How exactly legal it is to create emulators & fpga implementations of the cpus?
Last time i checked, WDCs website says that they provide licenses for fpga cores and such, so i ...

Hello

This is the topic that have probably been touched 1000 times before, but here i am, bringing it up again.

What good C compilers for 816 are there? To be good it needs to work(obviously) and produce efficient enough code(after all we dont have gigabytes of memory space to work with).

I've ...

Did you find this post and the one after? Might be helpful. There's going to be some puzzling-out needed, I suspect. It's late for me, now, but I could look tomorrow, see if I can help at all.
http://forum.6502.org/viewtopic.php?p=23982#p23982

Thank you for help :) i will try to figure it out, i ...

Is that Sam Falvo's? He only rarely drops by these days.
https://github.com/sam-falvo/lib65816

I did something minimal with that, once - doesn't make me an expert! Looks like Daryl (8bit) tried it too:
http://forum.6502.org/viewtopic.php?f=8&t=4275&p=47961&hilit=run65816#p47961

Or maybe you've ...

Hello

I want to use lib65816 in my project, and i am a bit confused on how to use it correctly. Is there any guide or documentation written for it?