[Help] PS1 don't reconize any CD

General information to do with the PlayStation 1 Hardware. Including modchips, pinouts, rare or obscure development equipment, etc.
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masmorra
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[Help] PS1 don't reconize any CD

Post by masmorra » October 23rd, 2020, 2:40 pm

Hello every one, I'm new here, I like to develop games and I'm trying to make some PS1 games (PSn00bSDK), so I bought one SCPH-1001, with broken laser.
So I bought a new laser KSM440-BAM from aliexpress (the broken one was this model), so I replaced, and every CD that I tried he start reading then stops. Always go to the menu screen (with Memory Card and CD player menu). I even tried a music cd, but no luck. The things that I tried:
  • Cleaning the lens (it is new, but cleaned with isopropyl alcohol)
It has a modchips, i don't know if is possible that it is causing this.

If anyone can help me, I appreciate that.

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Re: [Help] PS1 don't reconize any CD

Post by leafy » October 24th, 2020, 3:43 am

I have one I can't get going either.

Do you hear or see the sled move out? Do you see the audio tracks for an audio CD at the menu?

Test fuses and voltage regulators. http://diagramas.diagramasde.com/otros/ ... manual.pdf

make sure the laser power connector is not loose on the board

My post here shows how I tested various voltages. viewtopic.php?f=24&t=3660#p19735

what voltages are you getting on CN701, or better yet, at the motor wires as they attach to the motors?

I bought 10 new motor driver chips if you need to get one from me. They are the BA6397FP

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Re: [Help] PS1 don't reconize any CD

Post by masmorra » October 24th, 2020, 10:03 am

Hi!
leafy wrote:
October 24th, 2020, 3:43 am
Do you hear or see the sled move out? Do you see the audio tracks for an audio CD at the menu?
It moves only if i pull it a litle bit from center turning the motor with my hands. When I power on, it goes to the center. But I don't see any tracks even for audio CD.

The cd spins, the lens move up and down. At some point some cds even accelerate more than others, but nothing apperars on the audio cd menu.
Sometimes I hear some noise, I think its the lens snaping, but it depends on the settings I put on the BIAS or laser power.

I think all wires are well connected, I have disasembled and reasembled several times already. All of them are receiving power at least, because they all move at some point.

I will open it again and test these voltages.

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Re: [Help] PS1 don't reconize any CD

Post by masmorra » October 24th, 2020, 11:11 am

Power supply CN2, pins
1 - 7.41V
2 - 0 (GND)
3 - 3.41V
4 - 0 (GND)
5 - 3.44V
6 - 0 (GND)
7 - 3.35V

I don't know if this is in the correct order (1-4 right to left)
CN701, 1-4 door open / door closed with disc
1 SL- 3.42v/ 3.35v
2 SL+ 3.42v/ 3.25v
3 SP+ 3.42v/ 3.43 up to 4.0~5.0
4 SP- 3.38v/ 1.03 - 3.00 when disk is rotating (oscilates a lot), then go back to 3.38

The CN702 is a bit harder to measure, how you did it? remove the laser? And how I count the pin numbers? I'm a litle lost here.

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Mdv
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Re: [Help] PS1 don't reconize any CD

Post by Mdv » October 25th, 2020, 10:03 pm

the chinese lasers are no good, you are better off using the laser from a ps1 slim.

what's wrong with the original laser?

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Re: [Help] PS1 don't reconize any CD

Post by masmorra » October 26th, 2020, 11:04 am

Mdv wrote:
October 25th, 2020, 10:03 pm
the chinese lasers are no good, you are better off using the laser from a ps1 slim.

what's wrong with the original laser?
The lens of the original laser don't even move (up and down) trying to read the disc.

leafy
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Re: [Help] PS1 don't reconize any CD

Post by leafy » October 26th, 2020, 2:58 pm

I need to leave until Friday, but it sounds like the sled doesn't move out. You should see more drop on SL- and the sled should move. Basically the driver chip sends a PWM on SL- or SL+ to turn that crappy little motor one way or the other. So, it is possible that IC is blown. The one I mentioned above.

I measured my other connector pins using a long insulated probe. It can go under a spinning CD even if you angle it correctly.

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Re: [Help] PS1 don't reconize any CD

Post by masmorra » November 20th, 2020, 9:33 pm

Hi, after some time I found a guy that can make it work.
He told me some problems he found:
The chinese optical was not working
The original optical unit had the flat cable broken, so he replaced using some parts of the chinese one.

When I got it back was barely reading anything, so I tried to adjust the lens and after some testa o got it working with ~750mAh. I received it with ~592mAh.

So thanks guys for the help.

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