MM3 mod for PS1 has been a hassle.

Like TriMesh said, try the Laser in another Unit before tweak the pots because most stock pot settings works fine for good backups. Can you also please give us your backup disc MediaID ? Tools like IMGburn can show you that.

Actually there are PU-7 and PU-8 boards that come with a good servo unit, the SCPH-3000 does In my opinion its the best version, a nice DAC and a great laser but NTSC-J only.

 

Nevermind about the pots then. Also, it's reading discs again, but acting strange. It reads fine the first time I put the disc in... but after that, the experience gets worse the longer it goes, and second time it runs. It starts skipping a lot more, and sometimes stays on loading. Just now, it played through the first intro FMV for Wip3out (The psygnosis logo), but it's not loading the second one. During the first run, I managed to finish a race, but it stayed at the loading screen between the high score table and the menu. I've tried sticking the game into the system at the BIOS screen, but that only made it go to the PS1 logo screen a bit faster, w/ no in-game benefits

What should I do?

 

The boards used in the SCPH-3000 are the same as the ones used in early SCPH-1001s - I've seen plenty of bad ones in both machines, although they do work better than the really early PU-7s used in SCPH-1000s, mostly down to bugs in the mechacon code being fixed and the use of a different CD DSP (CXD2510 rather than CXD2516). They also have the annoying boot ROM that rejects non-Japanese discs and the old VRAM based GPU that does shading in a 5:5:5 RGB color space and tends to cause banding on shaded areas.

Technically the CD side of all the PU-7 and PU-8 boards are very similar - they all use a hybrid servo system with analog focus and tracking loops but a digital spindle servo. The first board with a fully self-adjusting digital servo was the PU-18 - it's just a pity that by that point Sony had started cutting corners for cost saving on a bunch of other stuff.

 

Could it be a heat thing causing the disc reading ability to deteriorate over a session? Like I said, it works fine at first but the ability for it to read my discs seems to get worse over the session.

 

On the earlier models, scph-100x to 3000 have the laser unit located very close to the power supply. The later models like the 5000 series have relocated laser unit on the right side of the CD bay.

 

Can you please give reference for this ? I'd like to read that

 

I will try and find my notes - this was stuff that I observed by examination of the firmware changes between the original "C0" mechacon code and the "C1" version that was used on the slightly later boards.

Some I can remember off the top of my head:

The original C0 code doesn't bother to cancel the servo sequencer at startup - so if you send the CD reset command while the servo seqencer is active the disc won't be recognized properly because the firmware state will be out of sync with the hardware state. This normally results in the focus servo losing lock on the next command and makes the whole process repeat.
There are a couple of places that the code doesn't set the "no disc" flag despite the inability to detect the disc.
In a couple of places the code sends commands to the servo amp that are either not defined in the datasheet or have the wrong parameter length.
The gain adjustment code has been pretty much completely rewritten in the C1 revision

None of this stuff will stop it from working, but tends to turn what should be recoverable errors into ones where the drive just completely loses track and has to open all the servo loops, move the pickup back to the home position and restart the whole disc access process (the most obvious sign of this is the clicking noise from the lens when the focus servo is shut down).

Edit:

OK, I just checked and the SCPH-3000 I was looking at was one with a 1-655-322-15 PU-7 board and the 424660 mechacon. This was still running the C0 version of the code, and is in fact that same mechacon chip that was installed in the late production SCPH-1000s - the internal date is 18th November 1994, so this revision is earlier than even the Japanese launch.

The older SCPH-1000s used a 424666 mechacon (I'm not sure why the older code has a higher number) which is dated 19th September 1994.

The C1 revision that was installed on the later PU-8 boards is dated 16th May 1995. It's possible there are other intermediate versions but I don't have any boards that use them. Can you have a look at your PU-7s and see what mechacon they have on them?

Changes between the 19th September code and the 18th November version:

Added: Check to stop motor and reset sequencer on startup or restart
Added: Code to set no-disc flag if lid open detected in main event loop

All the other changes I was mentioning were made in the C1 revision PU-8 code.

Out of interest, which pickups do your SCPH-3000s have? All the ones I've seen have had the older (plastic framed) KSM-440ACM with the later metal framed KSM-440ACMs introduced during the PU-8 era.

 

I could still use a solution for my PS1's ability to read burnt games degrading as a session goes on.

 

That really sounds like a bad laser diode to me - as the diode warms up the output drops, but if the control circuit is already running at maximum power because the diode is low output then there is nothing it can do and the readback quality just deteriorates.

 

It's been happening with both the original laser assembly and the PSone laser assembly I put in there. Old laser got to the PS1 logo consistently at first, but stopped beign able to do so as time went on during my testing sessions. The new laser reads the games fine, but loading times take longer as the gaming session goes on, eventually staying at a loading screen forever.

 

Have you got another console you can try them in? I guess it's possible that some other component (like the driver transistor for the APC amp) is temperature sensitive, but degraded read performance as the machine warms up is the laser diode nearly 100% of the time.

 

okay kiddo. this is your problem: THE DISCS. you've gone to all this trouble and swapping stuff around, but your symptoms are obvious re: what's going on here.

i have a 1001 with a lightly used ACM drive and it despises CD-R's. i have to burn onto champagne-grade Taiyo Yuden/JVC discs to even have a chance, and at 2x speed! good luck finding a burner that can go that low. my other machines, like my PSone and PS2 don't need such an absurdly low speed, but they still DEMAND taiyo yuden.

go get some JVC-brand discs, burn them as SLOWLY as you can with ImgBurn (or Nero if you want) and report back.

 

slow doesnt automatically equal better burns. Infact, slower can be worse.

Its a more complicated issue than most people realise. Its a balance of burner with media. It could just be your burner isnt very good with TY discs.

 

that's not what i'm talking about here. forget the burner itself for a moment. notice how TY discs have that distinctive blue bottom; that's due to a different dye that does a better job mimicking a factory pressed CD to a finicky laser like the one in a PS1. but most CD-R's have that light green bottom; that dye type simply does NOT work as well in a PS1 (or anything, for that matter) he needs either JVC discs or Verbatim DataLifePlus.

he has swapped out his mech with a BAM, correct? so he is halfway there. once he switches to TY, he probably won't have to burn all the way down at 2x to get working discs. (but still burn them slow) but you are not going to get far with those light-green phtalocyanine discs in a PS1. forget it.

 

No, I am directly replying to you and what you said and how its incorrect.

"burn slow" for best quality is nonsense. End of story.

 

darling, you don't even have a clue what you are replying to. i never actually SAID burning slow gives better quality. i said burning slow will get the discs to read better in a crappy PS1 mech. for all i know, they could be riddled with raw errors, but the PS1's laser is HAPPY. i'm trying to help this kid stop wasting his time and move on.

 

Clearly you do not understand how CDRs work.

Its all about burn quality (PIE and PIF) and jitter, these are the only variables that can be changed by the way the disc is burned. If you are saying to burn slow makes the PS1 read the discs - you are saying burning slowly guarantees improvementito the quality of the burn. Its quite that simple. (its also complete nonsense).

Maybe it works for you, with that specific media, with your specific burner. But if thats the case, then its just that your burner doesnt handle TY discs very well (or any discs, maybe its just crap). But "burn slow" can actually make disc quality worse - it all depends on the drive and its firmware for that specific media code. (writers do not burn all discs the same, they have a table in the firmware that checks the media ID of the disc and burns it to a writing strategy in the firmware)

I can tell you for 100% fact, that if I burned TY discs slow on my burner, I would get far worse quality burns (probably still work though, as my collection of writers were bought for specific media types and are generally excellent with the media they are paired with).

So rather than trying to be patronising, maybe you should research what you are talking about.

 

i would like to add Burner , Burn Speed , Burn Software and Media. I read on ClubmyCE forums low burn speeds can do more harm than good it was a sticky over at that forum. Also i've discovered that different software gives better results than others (less C1/C2 errors).

for slayer this has been covered early in this thread and not addressed by him , we have given our thoughts and knowledge on burning and it has been ignored. I can't help a person that isn't willing to follow our tips knowledge etc.........

 

you aren't wrong about anything you say, but none of what you say is relevant to my point.

we are not talking about error correction. i'm talking about REFLECTIVITY.

i don't know why, but burning on TY, at a slow speed, makes the mech in a PS1 read the disc better. i do not doubt that jitter is higher, and that errors are higher. but they are probably still within tolerances that the machine can handle, and thus are not an issue. the reflectivity of the resulting disc--in my experience, with my equipment-- is closer to what my PS1's want. therefore, i am strongly recommending he try the same approach. i don't know how to put it any simpler than that.

 

Burning your discs at 2x doesnt make them more reflective. Its probably reducing jitter (because your writer is crap with TY discs). But again, thats burn quality.

Like I said, you are talking about something you do not understand - which is no problem. Until you attempt to be a patronising dick. Then you shall be called out on it.