Search found 39 matches

by Akari
July 26th, 2016, 6:22 am
Forum: Research
Topic: Playstation GPU reversing [56k Warning]
Replies: 1
Views: 2958

Playstation GPU reversing [56k Warning]

Meanwhile we receive pictures of decapped GPU (without delayering yet). Old 160 pin GPU and RGB converter http://forum.emu-russia.net/download/file.php?mode=view&id=1207 http://forum.emu-russia.net/download/file.php?mode=view&id=1206&sid=05138a42fbb413b9ba6d0abd3a86400a Also here is working material...
by Akari
February 12th, 2016, 9:53 pm
Forum: Research
Topic: Playstation CPU reversing [56k Warning]
Replies: 68
Views: 68379

Re: Playstation CPU reversing [56k Warning]

Hello. How far has work on the DMA controller come? There are unused bit fields at the top (bits 31:28) of the DPCR (0x1F8010F0) register. They might belong to a DMA channel, controlled not through the standard registers in the DMAC range, but through dedicated registers in the address space of the...
by Akari
December 6th, 2015, 4:25 pm
Forum: Research
Topic: Playstation CPU reversing [56k Warning]
Replies: 68
Views: 68379

Re: Playstation CPU reversing [56k Warning]

I continued working on chip. Now my main target is DMA controller. I started from buffer which has 7 blocks with 8bits size. It has 3 address wire and that callow us to store and read 8 different bytes in each block. 8x8x7 bits in total. All data went to this buffer through flip-flops and multiplexo...
by Akari
May 4th, 2015, 3:28 am
Forum: Research
Topic: Playstation CPU reversing [56k Warning]
Replies: 68
Views: 68379

Re: Playstation CPU reversing [56k warning]

Do you plan to decap GPU, GTE, RAM and SPU later on? I think it'd be even more helpful for emulation than decapping CPU which was already pretty well known. The current theory is that the GTE is part of the CPU. But the CPU is huge, and at the moment, Akari and org are having analyzed the MDEC sect...
by Akari
May 3rd, 2015, 4:31 pm
Forum: Research
Topic: Playstation CPU reversing [56k Warning]
Replies: 68
Views: 68379

Re: Playstation CPU reversing [56k Warning]

PSXBA wrote:Also do you plan to ever go back to GTE reversing, judging from the ogamespec/pops-gte repository it seems to be still incomplete.
Noone ever tried to reverse CPU GTE. Org wanted to do this but he seems to be busy now. Pops-gte is his project too, I dont know if he ever will work on it again.
by Akari
May 2nd, 2015, 3:27 pm
Forum: Research
Topic: Playstation CPU reversing [56k Warning]
Replies: 68
Views: 68379

Re: Playstation CPU reversing [56k Warning]

These are just pictures where is an actual code like the the code available for CPU and think GTE on Github. Only photos of top level metal is available. This is not enough to start reverse of GPU. If you are interested we can asc our decaper to polish metal and take photo of M! and then polysilico...
by Akari
January 30th, 2015, 6:44 am
Forum: Research
Topic: Playstation CPU reversing [56k Warning]
Replies: 68
Views: 68379

Re: Playstation CPU reversing [56k warning]

Hey Akari, I'd like to help out more with the reversing and posted some stuff on the psxdev.ru board I upload lastest researched data to svn. Most interesting are in 00_control.odg This is core control circuits. Still don't know exactly how they works. Could you maybe have a look? That would be gre...
by Akari
January 8th, 2015, 9:07 am
Forum: Research
Topic: Playstation CPU reversing [56k Warning]
Replies: 68
Views: 68379

Re: Playstation CPU reversing [56k warning]

Reverse how cpu handles data that writen to register 1F801820h and readed from register 1F801824h 1F801820h register that controls MDEC. 1 - Decode Macroblock 2 - Set Quant Table 3 - Set Scale Table Martin's description is right: MDEC(1) - Decode Macroblock(s) 31-29 Command (1=decode_macroblock) 28-...
by Akari
January 4th, 2015, 9:27 am
Forum: Research
Topic: Playstation CPU reversing [56k Warning]
Replies: 68
Views: 68379

Re: Playstation CPU reversing [56k warning]

After small break i finish circuit that packes result bits of yuv to rgb conversion into 32bits words of result buffer. Circuit uses depth output bits from control register. http://forum.emu-russia.net/download/file.php?mode=view&id=1052 Found where register 1F801824 written and 1F801820 read from d...
by Akari
November 5th, 2014, 11:49 pm
Forum: Research
Topic: Playstation CPU reversing [56k Warning]
Replies: 68
Views: 68379

Re: Playstation CPU reversing [56k warning]

Real numbers used for YUVtoRGB conversion are: G=(-88/256 * B)+(-311/256 * R) R=(359/256 * R) B=(454/256 * B) Are you sure? That G formula doesn't look correct to me. According to the tests I ran a year or two ago on my SCPH 7002 unit, it should be: G=(-88/256 * B)+(-183/256 * R) Sorry, my mistake....
by Akari
November 5th, 2014, 7:01 pm
Forum: Research
Topic: Playstation CPU reversing [56k Warning]
Replies: 68
Views: 68379

Re: Playstation CPU reversing [56k warning]

Quick review about progress: YUV to RGB almost finished. Now I try to finish citcuit that pack converted data to 32bit buffer. Circuit integrated with IDCT control and uses stream of data from IDCT to speedup converting process. Thats overall progress for now ) http://forum.emu-russia.net/download/f...
by Akari
October 3rd, 2014, 10:45 pm
Forum: Research
Topic: Playstation CPU reversing [56k Warning]
Replies: 68
Views: 68379

Re: Playstation CPU reversing [56k warning]

Real numbers used for YUVtoRGB conversion are:

Code: Select all

G=(-88/256 * B)+(-311/256 * R)
R=(359/256 * R)
B=(454/256 * B)
by Akari
September 22nd, 2014, 5:26 am
Forum: Research
Topic: Playstation CPU reversing [56k Warning]
Replies: 68
Views: 68379

Re: Playstation CPU reversing [56k warning]

New update: still trqacing YUV to RGB. Last week it was a bit part of control logic. Now all cells are in upper 05 part, near RLE.

Image
Image
by Akari
August 30th, 2014, 12:13 am
Forum: Research
Topic: Playstation CPU reversing [56k Warning]
Replies: 68
Views: 68379

Re: Playstation CPU reversing [56k warning]

A bit of progress on YUV to RGB conversion. Data from UNIT20 (result from IDCT) expanded to 10 bits by duplicate bit 4 and 6. And then used in some multiplication. I can't get second multiplier yet. http://forum.emu-russia.net/download/file.php?mode=view&id=1010 http://forum.emu-russia.net/download/...
by Akari
August 23rd, 2014, 2:24 am
Forum: Miscellaneous
Topic: Experimental PS1 Wiki
Replies: 12
Views: 11709

Re: Experimental PS1 Wiki

Akari what's up with it? Do you want to keep it in russian, or are you going to switch to english GUI and agree to translate all pages to english? Maybe some people could help via google translate. Whatever way the translation is done, the goal should be to have all pages 100% in english, and every...
by Akari
August 22nd, 2014, 11:00 pm
Forum: Miscellaneous
Topic: Experimental PS1 Wiki
Replies: 12
Views: 11709

Re: Experimental PS1 Wiki

I don't see why we need a wiki. If you need to find something, just use the search built into the forums. The reason I started psxdev.net was because there are so many PSX 'development' based sites floating around with zero management and are not kept up to date whatsoever. http://wiki.psxdev.ru/ i...
by Akari
August 21st, 2014, 2:33 pm
Forum: Miscellaneous
Topic: Experimental PS1 Wiki
Replies: 12
Views: 11709

Re: Experimental PS1 Wiki

Maybe better will be translate and continue to work on this wiki http://wiki.psxdev.ru/
We already has a lot of information there. Mostly in russian, because we lasy to write in english.
by Akari
August 3rd, 2014, 6:53 pm
Forum: Research
Topic: Playstation CPU reversing [56k Warning]
Replies: 68
Views: 68379

Re: Playstation CPU reversing [56k warning]

What I tagged as "constant factor" is actually the factor 8 that is used with the very first element (it's probably 8 in order to compensate for the division by 8 in the following steps). Yes, I can confirm that first value (DCT) left shifted by 1instead of right shifting by 2 as usual values. So f...
by Akari
August 2nd, 2014, 11:32 pm
Forum: Research
Topic: Playstation CPU reversing [56k Warning]
Replies: 68
Views: 68379

Re: Playstation CPU reversing [56k warning]

In the center of the schematic we have the quantization table multiplier that multiplies the data with the elements of the quantization table/matrix. I am fairly sure that this is a variant of the Booth multiplication algorithm where instead of bit slices of length 2, we look at bit slices of lengt...
by Akari
August 1st, 2014, 4:02 pm
Forum: Research
Topic: Playstation CPU reversing [56k Warning]
Replies: 68
Views: 68379

Re: Playstation CPU reversing [56k warning]

mousefx wrote:Holy crap dude for whatever this is good, great work.
Shadow wrote:Absolutely amazing. Excellent work. I have changed your rank.
Thanks. Now I'm working on overall RLE control which links RLE with IDCT. Soon I'll post new screens )