ps2 laser questions (not the usual questions)

[scampo77]

i have questions about the lasers i cant seem to get answered anywhere online. i need to find the test points for the different versions of ps2 so i can adjust the laser using an oscilliscope. i have found a ton of websites saying that a certain setting is the most bestest setting ever for reading dvds or cds, 900,1000,1100,1200 etc ohms. does anyone know of a device used to measure the actual brightness of the laser? what is it called and where do i get one? also does anyone know if it is is possible to replace just the laser diode in the laser assembly? if its true where can i buy one?

my point is that all i can seem to find is hit and miss techniques to line up lasers and im looking for definitive answers to verify a working laser or correct alignment. i have measured resistance across focusing coils and played with white table screws for hours and put pot screws from 800 - 1500 ohms and still i have 5 lasers which wont work.

any legitimate help would help me out a great deal

[viletim]

There are tools available to measure laser output power but you won't be able to afford them. Anyway, it's adjusted buy the manufacturer of the laser assembly and unless you think you can do a better job, why would you touch it?

I recall somebody on these boards found a complete service manual for an ealrier model PS2, try a search. It'll help you with test points.

There are two diodes in a PS2 laser assembley, one for reading CD, one for reading DVD. If you can read one an not the other then you have a bad diode. If you can't read both then the problem is probably something else.

[scampo77]

well the reason i need to adjust it more accuratly is because i have several lasers that will work in one console but not another. i know they are weak but there must be a way to adjust it accuratly. if a laser does completly fail and i replace it with a new one there must be a way to align it perfectly so that the focusing coils arent bent all the way over to one side.

do you have the name of the "tools available to measure laser output power" and a guess as to their pricetag.

if the diode is bad can i replace just that component?

[NeWmAn]

the reason i need to adjust it more accuratly is because i have several lasers that will work in one console but not another.

Have you correctly reprogrammed the eeprom with the parameters of the lasers that you have been switching? Otherwise the new laser will only read CDs.

I've read that there's a way to tell if a laser is shot by replacing some resistors and measuring the voltage drop on them when a read is in progress.
I can't tell if it works because I've never tried it   

put pot screws from 800 - 1500 ohms

I wouldn't play much with the trimmer settings of the laser, if you go too low you WILL kill it!
Another (more important) thing to look is if the lens and mirror are clean and if the BA chips aren't dead/damaged (don't forget to use the heat spreader pad!)

if the diode is bad can i replace just that component?

It is doable, same as it is doable to replace the worn out tracking coils. Have seen to-do guides, but with the current value of a used PS2 is not worth it anymore.

[l_oliveira]

Is it illegal post the service manuals ? I do have manuals for at least 10 different kinds of PS2 motherboards.

[scampo77]

please email me at scampo77@gmail.com i would absolutly die for the service manuals. i dont see why it would be illigal.

where did you read about replacing resistors? im not sure how a SMD resistor could breakdown over time they are usually an on/off sort of thing.

i suppose the main thing i am after is to be able to say "this laser is at 86% that of a brand new laser" my experiance of replacing the focusing coil assembly seems pretty fruitless when i am working with a laser diode that is operating at 9%

[kendrick]

While it's probably not iilegal to post the service manuals, we're not exactly set up to manage that kind of content. Over at http://www.assemblergames.com/ they tend to collect official development data like spec sheets and service manuals, and they have a whole forum dedicated to archiving that stuff.

[NeWmAn]

where did you read about replacing resistors? im not sure how a SMD resistor could breakdown over time they are usually an on/off sort of thing.

I've read it on some forum, there was the attached photo and a description on how it is supposed to work:

1) Put a dvd in the drive and start it
2) Set your multimeter to volt and measure the 4 * 220 Ohm resistors closer to the small CDX (in the photo those are in the red rectangles)
3) Divide the value measured by 11. The result should be closer to 60.
In the photo you can see the modification to trim to 0
In the red rectangles there were the parallel resistors
If the values are far from 60 the diode is dead

IMHO this is not clear at all, but as I already written I've never tried it. Maybe l_oliveira knows more about it?

Over at http://www.assemblergames.com/ they tend to collect official development data like spec sheets and service manuals, and they have a whole forum dedicated to archiving that stuff.

Can you browse and access the data without being a registered member? If not I would advise against posting on ASSEMbler form and instead use http://www.eserviceinfo.com/
(that's the place where is the ps2 schematic mentioned above).

[l_oliveira]

Now that's a useless mod...    You're changing a circuit that is dynamically controlled by a microprocessor. (that's the power driver for the two laser diodes, btw)

The Texas instrument chip close to that circuit is the RF frontend processor (converts analog output from the optical diodes into digital data stream and also control the laser parameters following commands given by the Mechanics Controller through a serial command bus)

If you change the electric current limiter resistors, all the PS2 will do is put more power on the lines making it up for the added resistance in the circuit.
The mechanics controller on a PS2 analyzes two values before figure out the current it has to drive to the laser diode: Eeprom settings and the resistance of the variable resistor at the bottom of the laser unit.

With the sony tools one can adjust just the eeprom and don't even need to tweak the pots. Since the PS2 all Sony game systems have a serial port for adjustment of the laser drive (even the PSP has it) and all settings are stored on a eeprom.

so a adjust process would go around:

1- adjust the mechanism using preset values instead of eeprom and adjust discs (special glass discs for optical adjustment)
2- test the mechanism using preset values and test discs
3- adjust the eeprom using the proper software tools and test discs (same discs used for the first test)
4- test with normal discs for proper operation.

[NeWmAn]

Since the PS2 all Sony game systems have a serial port for adjustment of the laser drive (even the PSP has it) and all settings are stored on a eeprom.

so a adjust process would go around:

1- adjust the mechanism using preset values instead of eeprom and adjust discs (special glass discs for optical adjustment)
2- test the mechanism using preset values and test discs
3- adjust the eeprom using the proper software tools and test discs (same discs used for the first test)
4- test with normal discs for proper operation.

Are the official tools to do the calibration available or is it lenschanger the only thing that's around?

Regarding the mod described above:
as I've already written it's not clear at all, just the 60*11 Volt doesn't make much sense to me... And (according to the text) it isn't supposed to be for regulation but instead to check  if a laser is dead or not.

[scampo77]

3- adjust the eeprom using the proper software tools and test discs (same discs used for the first test)

where do i find a test disc? how do you actuaally adjust an eeprom chip? the only eeprom i am familiar with are the ones in a car and i change them using another computer. would this be the same way?

so is there a tool to measure laser "brightness" ?

these 4 steps for adjustment, is this the normal way to get any other laser to work? like a gamecube or xbox or a dvd player?

when i change the value on the pots what am i changing?

[l_oliveira]

You put the PS2 on test mode by connecting a test pad a signal to GND (It will show a color bars pattern on the screen and play a single tone test sound)

Then you connect the PS2 VD drive to a PC through RS232C. Sony programs for windows 98 will then be used to perform the tasks I described on previous post.  The adjustment discs are standard for adjusting DVD and CD players and Sony sell them. The test discs are PS2 specific as they contain programs to test the motherboard along with usual testing pattern data similar to the ones found on the adjustment discs.

Nyuman, the lenschanger tool was made by a friend of mine after he studied the official DVD drive adjustment tool throughly. The Sony tool don't give any access to the eeprom contents. It just does tell the DVD drive CPU when and which adjustments are to be made and also tell it to store the settings on the eeprom once they're done. The DVD drive CPU is capable of auto adjusting, but it's designed to aways use the data on the EEPROM on boot even it it does self adjust after a while working. It's done that way so the PS2 won't "last forever" and you end having to take it for service after a year or two of use.

And let me repeat here. The PS2 is intentionally designed to fry if the user is using recordable media. Be it the tracking coils or the laser diodes(again, it has two laser diodes). It will eventually fry early if people insist on using DVD-R or CD-R with it.

[NeWmAn]

Thanks for the info

The PS2 is intentionally designed to fry if the user is using recordable media

I've read/heard this many times, especially after V9 and newer PS2 came out. The interesting fact is that starting with that model the DVD-R and DVD-RW were (supposedly) officially supported

You put the PS2 on test mode by connecting a test pad a signal to GND (It will show a color bars pattern on the screen and play a single tone test sound)

When a PS2 shows the test mode by herself, is there something that can be done to repair it?

I have a few more questions for you, I hope scampo77 doesn't mind

1) Is it possible to change a PAL PS2 into a NTSC via a simple bios chip swap? (same PS2 model)
2) If you get the error "DVD player is not installed" (or something like that), what is the problem?
3) Do you have any tech docs about repairing/servicing a PSX DESR-5100

[l_oliveira]

Thanks for the info

I've read/heard this many times, especially after V9 and newer PS2 came out. The interesting fact is that starting with that model the DVD-R and DVD-RW were (supposedly) officially supported

When a PS2 shows the test mode by herself, is there something that can be done to repair it?

I have a few more questions for you, I hope scampo77 doesn't mind

1) Is it possible to change a PAL PS2 into a NTSC via a simple bios chip swap? (same PS2 model)
2) If you get the error "DVD player is not installed" (or something like that), what is the problem?
3) Do you have any tech docs about repairing/servicing a PSX DESR-5100

First things first...  The 50000 and newer do indeed support DVDR but *only under DVD Video playback*
With a modchip installed you force it to play the discs as GAME and the DVD drive CPU knows it's running a DVDR as data (non video) disc so it is programmed to crash under certain circumstances, causing the tracking coils to melt (burnt coil syndrome)

Now for the questions:
1)It is possible but you need to: Swap the bios for the target region bios; switch the DVD drive CPU for one compatible with the target region and swap or rebuild the DVD drive EEPROM matching with the target region. I've done this and it does work. Swapping the DVD drive CPU is enough to make it boot the game discs of the target region but some portions of the bios (DVD Player mostly) are encrypted with region specific crypto and will be broken.

2) The bios cannot read the "EROM" (encrypted ROM) for some reason. The PS2 bios is programmed to behave that way if no DVD driver exists internally. It will require a DVD driver installed on a memory card. 
There might be a short circuit on one of the bios pins which prevents the PS2 from reading it's second half.

3) Sadly I don't... I don't ever saw one live. Just pictures.

[scampo77]

where can i get more information on the software and hardware used for these adjustments? if i do insist on running dvdr media i need to be able to replace the laser diode and i need to be able to adjust it. more impostantly i need to figure out a way to see the difference of a laser at 86% of its life and a laser that looks identical but is at 84% of its life.

what is the purpose of a potentiometer on the bottom of the laser? it seems i get a lot of answers like "it makes things good" and "dont turn it too far" but no where else i have posted has been able to tell me

are oscilliscopes used for any laser adjustments? i have one waiting for any sort of info to get it going.

does anyone have a link to place i can purchase sony adjustment discs?

l_oliveira mentioned that "You put the PS2 on test mode by connecting a test pad a signal to GND (It will show a color bars pattern on the screen and play a single tone test sound)" is it possible to elaborate on this. i have never heard of doing this before and it seems to be a very useful bit of information.

last question, is it possible to buy a new laser diode and just pop the old one out and pop a new one in?

is it possible to gethold of the lens changer tool that you spoke of?

l_oliveira is it possible to post a link to the server where the ps2 service manuals are? i cant find it anywhere

thank you very much to all the posts i got i have been looking for this information for about 3 years and i have put up dozens and dozens of posts tryiing to find anyone who knows anything and in the last 8 posts here i have made more progress then the last 3 years. thank you to everyone

[NeWmAn]

Calibration with Oscilloscope: You can find some info if you Google for it, for example this pdf:
http://www.eletronicosforum.com/cursos/video_game/playstation/Sony_Playstation+2+-+Calibracao+do+Laser.pdf

Lenschanger: I only got an old version of it , again you can find it easily if you Google for it (although most places need registration to download).
Be aware that you need to be able to execute unofficial code (i.e. modchip or exploit) to use it.
If you were swapping different kinds of lens between different models of PS2, without using Lenschanger afterwards, it' no wonder they weren't working.

what is the purpose of a potentiometer on the bottom of the laser?

It changes the voltage that powers the diode, lots of info here: http://www.repairfaq.org/sam/laserdio.htm

if i do insist on running dvdr media i need to be able to replace the laser diode and i need to be able to adjust it.

If your PS2 model is 50000 or newer and you are using copied games it would be wiser to do some modifications to save your PS2.

1)It is possible but you need to: Swap the bios for the target region bios; switch the DVD drive CPU for one compatible with the target region and swap or rebuild the DVD drive EEPROM matching with the target region. I've done this and it does work. Swapping the DVD drive CPU is enough to make it boot the game discs of the target region but some portions of the bios (DVD Player mostly) are encrypted with region specific crypto and will be broken.

Too much work I only wanted to run BB Navigator and enable HD save/install for the JPN games that allow it.
I have a dead JPN PS2 (defective GS) and I've tried putting the bios into an EUR PS2, but I got the "dvd driver not present error".
At the time I thought a simple bios swap wasn't enough, so I put back the EUR bios but I got again the "dvd driver error".
It turned out that the EUR PS2 was defective from the beginning , So after this I was a bit pissed off and I didn't try the swap again.
BTW. JPN and EUR have the same region coding for DVD (2), I though that maybe with a modchip I could bypass any region protection...Is it really necessary to swap the DVD drive cpu and EEPROM in that case?

[l_oliveira]

Actually no, they *don't* have the same region (PAL region 2 is not really the same thing as NTSC region 2 on Sony terms)
Because the "region" that matters on this case is the magic gate encryption key which varies with the DVD player region.

For example Asia consoles bear NTSC J marking and will play japanese games but the utility discs won't work in them (You can't use the japanese HDD with them, for example) Like I said... Replacing the mechanism controller would make the japanese utility discs work on your console. You would not even need to replace the bios I believe.

Ever since the hackers at psx-scene figured out how to boot elf files on unmoded consoles exploiting magic gate encypted executables (KELF) this mechanism has been understood fairly well.

[phreak97]

can you elaborate on lensechanger? can it be used to fix a console with a laser that is still working but poorly?

is there a mod that can be done so the laser is self-adjusted from boot?

[scampo77]

the lasers do adjust from boot. it is the job of the focusing coils.

[l_oliveira]

can you elaborate on lensechanger? can it be used to fix a console with a laser that is still working but poorly?

is there a mod that can be done so the laser is self-adjusted from boot?

It's just that each type of laser (Sanyo HD7 or Sony 400x series) have different weight on their lens assembly. To compensate this boards starting on GH-015(the modchip pirates call it the "Version 5")  have a mechanism controller whose firmware can work with both, but the information of which kind is installed to the console is saved in the EEPROM. Lenschanger function is change that data so the laser type can be changed.

I advice to not use lenchanger unless it's absolutely needed *and* a backup of the eeprom data *needs* to be done before applying any changes to the eeprom data.

[scampo77]

all the info i can find on scope laser adjustment is very general and is all for either japanese or eur consoles. i cant find test points for any american released mother boards. ive spent about 2 years posting and looking.

the questions i would love answers for are ...

1) is there a way to measure the brightness of a laser so i can compare it to other ps2 lasers? if so where do i get that tool?

2) can i use a scope to align a laser (on N. American ps2's) so i can definitivly tell the laser is focusing and aligned ? where do i get info on this?

3) is it possible to replace only the diode in the assembly? then hopefully do the first 2 steps for adjustments.

thanks you very much for the link on the diode pot adjusments but it seems quite technical. i was hoping someone might be able to answer "what the pot on the laser is for" in more real world words. it seems to be a popular theroy that its like a dimmer on a lightbulb the more you turn it up the better it works, till it fails. from the little i know about lasers this doesnt really make any sense. even if this were true i would think that it would make the surface area of the beam smaller and therefore need to be adjusted. of all the repairs i have done on these i have never once had a DRE fixed by adjusting the pot resistance. maybe im just unlucky.

how many different 400x versions of lasers are there? A,B,C ?

[l_oliveira]

1) I don't know where you can get them but they're expensive and not specific for the PS2.

2) Yes you can and all you need is a schematic diagram for the board you're working with it. Region doesn't matter, just match the "chassis type" and the right service manual

3) Yes and I've done it countless times. Because the laser diode contains not only the diode itself but also the photodiodes, prismatic mirror and one of the collimation lens it's position relative to the rest of the mechanism is not critical. Making it possible to be replaced without advanced tools.

The tricky part about laser replacement is find a known good laser diode.

About the "dimmer" thing, there is two reasons that cause me to completely agree with you:

1- the lasers are powered with a automatic gain control system that makes sure their beam is constant regardless of the operation temperature.
2- newer systems (most DVD based systems and recent CD stuff) like the PS2 have a second feedback for the laser beam, from the photodiodes. That allows for reliable reading of R and makes it possible to read RW media. The drawback is overcurrent on the laser diode which results on shorter life cycle of the laser diode.

Tweaking pot on a new system is something only a "fucking pirate" would do, but on a old PS2 that's already having read issues on original discs is a mean to extend it's life for a little bit. That's the sole reason the PS2 has pots on it's laser.
To let people without custom tools adjust the laser power.  It's just that the results people get from tweaking the pots on dying systems make them behave that way on the forums/posts. 

About the lasers, I know the following types:

Sony:
KSS400A (SCPH-10000/SCPH-15000 A-Chassis)   Earliest type of laser. 400B will work on these units just fine.
KSS400B (SCPH-18000/SCPH-3000x AB, B, C and D-Chassis)   D-Chassis (v4) can use 400C laser just fine.
KSS400C (SCPH-3000x/SCPH-3500x/SCPH-3700x/SCPH-3900x/SCPH-5000x    E, F, G, H and I-Chassis)  These units can use Sanyo HD7 laser too.

Sanyo:
HD7 type 1 (SCPH-3000xR)   Any board above GH-015 (E-chassis) can use HD7 lasers /  Old laser diode chip (Same laser diode as 400A/B)
HD7 type 2  (SCPH-3900x)   New laser diode type (Same laser diode chip as 400C)
HD7 type 3 (SCPH-5000x)   Same as HD7 type 2 but has epoxy body instead of metal


On Sony lasers one can tell the kind of the laser diode by noticing the color of the border of the lens.
White border means old laser diode while yellow means new laser diode.  The laser chips have different optical polarity so a laser body for one type will not work with another unless you re-adjust the collimation lens.