"Please insert a Playstation CD ROM"

Discussion in 'Repair, Restoration, Conservation and Preservation' started by Teran, Jan 9, 2018.

Tags:
  1. Teran

    Teran Member

    Joined:
    Jan 9, 2018
    Messages:
    7
    Likes Received:
    0
    Hi everyone,

    This is my first post here. Not sure if this is an appropriate forum or even board.

    I recently purchased a PS1 and had some disc read issues with it pretty early on. Both with PS games and audio CDs. One thing led to another and I was pretty certain the CD motor was too weak. Also noticed what looked to be a mod chip that had a wire come undone, about the time it stopped reading anything at all. So stupidly, I yanked the wires out on that to try and take it out of the loop. No dice. Replaced the CD assembly and audio CDs are fine now. Game CDs will spin up, but now I get the "Please insert a Playstation CD ROM" message when using any normal, genuine US PS1 game. Never had that before. I think I fixed one problem and caused another.

    Anyway, have not found any details about this chip anywhere else. I am wondering if it's a PAL motherboard and it was modified for NTSC? I really don't know, I don't have any experience modifying or repairing playstations.

    This is a SCPH-5501. I'm in the US, so NTSC and US region coded games. Not looking to mod it or anything like that, just want to keep playing Chrono Cross and the like.

    So the chip I yanked off has a board and four pins with red, yellow, green, and black wires.The chip reads: CF745 - 04/P 9823SAJ.

    I can tell where the red wire went and the yellow wire is fairly obvious to me. I think the black might be right next to the red but I'm not certain. Green, no idea.

    Could you tell me what this chip is for? Is it OEM? What's the best way for me to fix this?

    Here's an album of potato-quality pictures, featuring the top and bottom of the board, along with the chip: https://imgur.com/a/L8jZL

    Thank you for your time.

    -Teran
     
  2. TriMesh

    TriMesh Site Supporter 2013-2017

    Joined:
    Jul 3, 2008
    Messages:
    1,910
    Likes Received:
    451
    From the look of it, it probably is a mod chip. A few things you could check:

    On the back of the board, look at that 52 pin QFP - one of the markings on it should be a C followed by a 4-digit number, like "C 2030" - the first 2 digits are the region of the discs it's designed to boot (10 = NTSC:J, 20 = NTSC U/C, 30 = PAL)
    Next to the link connector there should be some sets of resistor pads marked "JUE" - these also indicate the region the board was built for, although in some cases they are not installed. Obviously, on a NTSC:U/C board the "U" resistor should be soldered.
    Check the position of the pot that's in the lower left corner of the board in your top photo (I think it's RV703) - it's possible it's been turned right down to the counterclockwise limit to prevent the wobble on the disc from interfering with the mod chip.
    Also examine that area of the board on both sides to make sure no traces have been cut - this was also sometimes down to prevent interference with the chip.
     
  3. Teran

    Teran Member

    Joined:
    Jan 9, 2018
    Messages:
    7
    Likes Received:
    0
    Thank you for your reply. That was very helpful.

    The QFP? (not sure what that stands for) is indeed a C 2030. The U resistor is also the only one present.

    RV703 looks just like the potentiometer in this picture: http://jpegshare.net/images/0b/56/0b56c104634ce47e29383ed6ffe107a3.png

    However, I cannot seem to turn it in either direction to indicate whether it's been adjusted or not. Using that picture as a reference, the "10 16" capacitor due NW of the potentiometer has solder marks. On closer inspection, I think that a wire ran into the pin hole directly above the 'C' in CL710.

    I have not been able to find any cut pin contacts between any chips and the board.
     
  4. TriMesh

    TriMesh Site Supporter 2013-2017

    Joined:
    Jul 3, 2008
    Messages:
    1,910
    Likes Received:
    451
    OK, so you definitely have a US spec board - and that "C 2030" is exactly what I would expect to find on a NTSC:U/C PU-18 board. QFP means "Quad Flat Pack" - it's just the name of the sort of package that IC is in.

    OK, if you look at the pot there should be a flat part on the rotor - where is it compared to the 3 leads?

    It would also make sense for one of the wires from the mod chip to be soldered to that via above the pot - that's the trace that carries the digital version of the wobble signal and hence where you would connect the mod chip output.

    I assume that photo isn't your board? Because that one does have a cut trace in it - just to the right of that via.
     
  5. Teran

    Teran Member

    Joined:
    Jan 9, 2018
    Messages:
    7
    Likes Received:
    0
    Gotcha, I see what you mean about the chip package.

    The flat rotor seems to be facing South, West, West. Relatively speaking. So closest to the bottom left lead, the one in between the others.

    Oh, I see what you mean about the cut trace. Yes, that photo is not mine. Just a much better quality photo than I can take right now.

    I was looking for cuts between chips and the board at first, not cuts on the traces themselves. I can't tell if that same section is cut or not. It looks like most likely not, but it's hard to tell. I don't think it would be as the yellow wire seemed to be going from the top end of that trace. If you follow that line past where it's cut in the picture, the other end had a single copper strand still hanging on. I imagine if that were cut, it'd do no good.

    This is sure a good test of my eyes.

    Thank you for your help!
     
  6. TriMesh

    TriMesh Site Supporter 2013-2017

    Joined:
    Jul 3, 2008
    Messages:
    1,910
    Likes Received:
    451
    OK, that pot position sounds reasonable (from the description, it's similar to the one in that photo you linked?)

    Do you have a meter? There is a little 16 pin chip on the back of the board pretty much where that pot is - try checking for continuity between pin 1 of that little 16 pin chip and pin 17 of the mechacon chip (the QFP) - they should be wired directly together.
     
  7. Teran

    Teran Member

    Joined:
    Jan 9, 2018
    Messages:
    7
    Likes Received:
    0
    Yes, same as the photo.

    Looks like my meter is about 400 miles away. I've ordered another but may take it to a friend who has one. I'll check for continuity there. If there isn't continuity between the two, would a jumper wire likely solve it?
     
  8. TriMesh

    TriMesh Site Supporter 2013-2017

    Joined:
    Jul 3, 2008
    Messages:
    1,910
    Likes Received:
    451
    Well, it's just a check to see if the signal was interrupted (which is commonly the case if you are driving it with a modchip) - you could try just soldering a jumper between those two pins and seeing if the console boots.

    The trace on the other side of the board is very short - basically from that via and about 3mm to the chip - so it shouldn't be too hard to inspect it visually.
     
  9. Teran

    Teran Member

    Joined:
    Jan 9, 2018
    Messages:
    7
    Likes Received:
    0
    Ok, looks like pin 1 and pin 17 conect via that scratched out trace in this picture (not mine): http://jpegshare.net/images/0b/56/0b56c104634ce47e29383ed6ffe107a3.png

    On my board that whole trace looks to be scratched off. Is that even possible? The line is really well defined on that board, but on mine it's very faint, just looks like a trench in the board with nothing in it. I'll see if I can jumper it with what I have on hand.
     
  10. Teran

    Teran Member

    Joined:
    Jan 9, 2018
    Messages:
    7
    Likes Received:
    0
    The 3mm trace looks fine, just not the one between if I am reading it right. Also, you mentioned the board booting. The board does boot and play audio CDs, just no games. Might this let it load a game or is this a different problem?

    Thanks!
     
  11. TriMesh

    TriMesh Site Supporter 2013-2017

    Joined:
    Jul 3, 2008
    Messages:
    1,910
    Likes Received:
    451
    That track carries the signal that the CD-ROM controller MCU uses to identify the disc as being "licensed" - if it's broken then the drive will correctly identify (and play) audio CDs but all CD-ROMs will come up as being "Not a PlayStation CD" even if they are valid original discs from the correct region for the console.

    So if that trace really is ripped off the board then the behavior you are seeing is exactly what you would expect.
     
  12. gladiator5

    gladiator5 Robust Member

    Joined:
    Jun 25, 2012
    Messages:
    257
    Likes Received:
    15
    And A modchip will fix that problem? Cause it insert the hash that it is a licenesed disc?
     
  13. TriMesh

    TriMesh Site Supporter 2013-2017

    Joined:
    Jul 3, 2008
    Messages:
    1,910
    Likes Received:
    451
    Yes - sending the correct datastream on that pin while the CD-ROM controller is identifying the disc will get it recognized as a PlayStation CD-ROM. The correct data is different for each disc region, so this also generally defeats the regional lockout (it's not 100% - some machines, like the Japanese consoles, have a secondary region check).

    The data is just a 4-character ASCII string sent at 250 baud with one start and one stop bit. The required values are "SCEI" (NTSC:J) "SCEA" (NTSC:U/C) or "SCEE" (PAL) - this is where that 4 character string printed under the "Licensed by" text on the black license screen comes from.
     
    gladiator5 likes this.
  14. Teran

    Teran Member

    Joined:
    Jan 9, 2018
    Messages:
    7
    Likes Received:
    0
    Hi Trimesh,

    Great news! We soldered a jumper between those points where the trace was ripped out, connecting pin 1 and pin 17 like you said. Audio CDs and games work now.

    Thank you so much for your help. I really appreciate it.
     
  15. TriMesh

    TriMesh Site Supporter 2013-2017

    Joined:
    Jul 3, 2008
    Messages:
    1,910
    Likes Received:
    451
    Ah, cool - nice to hear that. Have fun with your games!
     

Share This Page