Table of cycles

[Qwe]

Hi friends,
Where can I find the table of cycles for each instruction of the cpu?

Thanks

[Tezz]

Hi friends,

Where can I find the table of cycles for each instruction of the cpu?

Thanks

Hi,

 

I usually refer here when cycle counting

 

http://www.6502.org/tutorials/6502opcodes.html

 

regards,

Tezz.

[Qwe]

Thank you Tezz.

Umh...I'm not sure the table mentioned above is applicable to Sally.
I remember that indirect addressing was very slow on atari 8 bit (about 40 cycles) and that table is a lot optimistic...but may be I remember incorrectly.

[Rybags]

The 6502 datasheet/manual has a decent one. There's opcode tables around that have the instructions on a 16x16 grid with cycle counts, operand size etc.

 

Atari's 6502 is the same as the other legacy ones - ie they all suffer 1 lost cycle for branch over page boundary and indexed reads over page boundary.

65C02 in fact is slower for some instructions when in Decimal mode - but the N flag works properly when in D mode.

 

There's probably better ones around but here's the PDF 6502 manual I have: 6502.pdf

Edited November 27, 2014 by Rybags

[Rybags]

Also note if you're cycle counting for the purpose of timing events that you should also consider Antic DMA activity which is highly variable depending on graphics mode and if PM graphics are active.

Grab the Altirra hardware manual for some good info there.

[flashjazzcat]

And Altirra's debugger will count cycles for you. Execution History: Right-Click->Timestamp Format->Show Cycles.

[xxl]

undocumented Sally (6502C) opcodes: http://xxl.atari.pl/?p=824

[Qwe]

Thank you very much

[Xuel]

Trevin Beattie's site is nice quick hardware reference for A8. His opcode table is fairly concise but uses different names for the undocumented opcodes than most others.

 

6510 references are also applicable, e.g. C= Hacking.