Comments on: The weird and wonderful CIC

By: A small recap, part 2 » project sd2snes

A small recap, part 2 » project sd2snes — Tue, 16 Aug 2011 05:55:41 +0000

[...] Segher reverse engineered the SNES CIC and published the disassembled ROM dump of the D411 (US/JP CIC). I figured out the seeds of the D413 (EU CIC) – just one nibble was changed – and made a PIC based CIC replacement with automatic region fallback. sd2snes now worked on any unmodified SNES. (Also a pendant was later created to replace the original CIC in the console itself – with additional features like switchless 50/60Hz switching. See the SuperCIC page.) [...]

By: SNES Super CIC SNES Switchless Mod! - ModControl.Com - GermanysNr1MultiConsoleSceneSource

Mon, 05 Jul 2010 09:28:01 +0000

[...] [...]

By: Segher

Segher — Sat, 03 Apr 2010 01:58:26 +0000

> i know lbli sets the low nibble of the ram pointer does lbli also set the port number?

From the big table:
46 out “output”, PN := A
“PN” means “I/O port number BL”

So yes.

> what do you mean when you say two’s or one’s complement?

The standard stuff. I suppose even wikipedia will give you the correct answer.

> when you say exchange/swap do you mean trade both ways?

I suppose so, “trade both ways” isn’t exactly clear to me.

> i found an error up top “set emmory”

Fixed, thanks.

> thanks again for helping me out

My pleasure. Please note that the instruction table shows *exactly* what the insns do; also, you can look at my emulator if you aren’t sure.

By: james

james — Wed, 31 Mar 2010 22:11:50 +0000

thanks segher that helps me a lot

i know lbli sets the low nibble of the ram pointer does lbli also set the port number? it seems too if it doesn’t how does the port number get setup?

what do you mean when you say two’s or one’s complement?

when you say exchange/swap do you mean trade both ways?

i found an error up top “set emmory”
thanks again for helping me out

By: Segher

Segher — Sun, 28 Mar 2010 17:30:42 +0000

james:

Yes, 78..7f take two cycles because they are two bytes long; the CPU fetches one instruction byte per cycle.

If an insn is skipped, it is still fetched. So it still takes a cycle; it isn’t executed though.

You can look at the emulator in my git repo (dis-cic.git), it is cycle-exact as far as I know (it is for the various NES CICs at least).

By: james

james — Sat, 27 Mar 2010 11:22:19 +0000

hey can you clarify a couple of things

all instructions are 1 cycle except $78 and $7C because they are two bytes?

if the skip condition is false does it takes 1 cycle for the “skip instruction” plus the next instructions cycles?

if the skip condition is true does it use 2 cycles? one for the “skip instruction” and the other “nop”?

By: Masyanya

Masyanya — Wed, 24 Feb 2010 07:54:55 +0000

WiiMAnWB… What what “CRC chip”?
Whats a f..king crap you route? On this link about CIC only few strings, and all of that already writen on top of this topic.
In this case i can posts this: http://gbx.ru/index.php?showtopic=47624&hl=
Nothing more comments…

… “Segher” GREAT MAN. He make disassembled CIC FIRMWARE, and instructions set for this chip, but not all instructions fully undestanded for me…
I’m build reversed CIC 6113 (Used ATMEL 8bit AVR core), based on this disassembed Firmware, original 6113 and my revesion work same, but no equal, and i need some corrections in instructions set to finish reversion… and I asks Segher spent some more time to correct my instructions set… if he can… /*be ashamed*/

By: WiiMAnWB

WiiMAnWB — Fri, 19 Feb 2010 15:47:43 +0000

http://emu-docs.org/Super%20NES/Cartridges/sfcdev2.php

this is everything about the crc chip you need to know.

By: Masyanya

Masyanya — Tue, 16 Feb 2010 20:39:11 +0000

hire instructin set image: http://mediapix.ru/pics/c6d67494dcb5a593c120afce7b7fefc3.gif

By: Masyanya

Masyanya — Tue, 16 Feb 2010 20:38:09 +0000

…not so…
Hmmmm, …thanks.

Please help me correct instructions SET, if you have some free time…