PS1 Which modchip works better for PlayStation 1 games?

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helakustorm

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From your point of view which modchip works better for PlayStation 1 games when you use PlayStation 1 or PlayStation 2?

I'm more interested in the ones we all know like MM3/Mayumi v4/ONEchip/PsNee for PS1 PAL/NTSC and Matrix Infinity 1.93/Modbo 1.93 for PlayStation 2 PAL/NTSC.

I own two PlayStation 1 PAL (SCPH-102 with PM-41 and PM-41 (2) boards; the latter one is modded with ONEchip) and two PlayStation 2 PAL (SCPH-77004 modded with M7 MP-788 and SCPH-90004 modded with Modbo 1.99).

Someone told me that the best combination for PlayStation 1 games is to use an SCHP-101 with ONEchip because it has the best compatibility ever.

What do you thing guys?

Thanks!
 
For PlayStation 1 games, it really doesn't matter - all the modchip needs to do is to allow the game to boot. The console I personally use is a SCPH-5552 with a dual oscillator modification and PSnee installed. There are a number of reasons for this:

1) It's got the new GPU, so less banding
2) Since it's got the SCEE boot ROM, a lot of games will just disable their anti-mod protection anyway
3) PSnee only sends data when the machine is reading the ToC, so it's highly stealth
4) On those early machines (before PU-22 / SCPH-750x) there is no interference between the modchip and the CD drive
5) With both oscillators installed, it has accurate timing in both PAL and NTSC modes
 
Trimesh said:
For PlayStation 1 games, it really doesn't matter - all the modchip needs to do is to allow the game to boot. The console I personally use is a SCPH-5552 with a dual oscillator modification and PSnee installed. There are a number of reasons for this:

1) It's got the new GPU, so less banding
2) Since it's got the SCEE boot ROM, a lot of games will just disable their anti-mod protection anyway
3) PSnee only sends data when the machine is reading the ToC, so it's highly stealth
4) On those early machines (before PU-22 / SCPH-750x) there is no interference between the modchip and the CD drive
5) With both oscillators installed, it has accurate timing in both PAL and NTSC modes
Click to expand...

What do you mean with new GPU?

In my case with SCPH-102 modded with ONEchip do you think that can I come across a game that will not boot because of the ANTI-MOD protection?
If yes, can you tell me what game/games are?

Thanks!
 
helakustorm said:
What do you mean with new GPU?

In my case with SCPH-102 modded with ONEchip do you think that can I come across a game that will not boot because of the ANTI-MOD protection?
If yes, can you tell me what game/games are?

Thanks!
Click to expand...

When Sony first produced the PlayStation, they used a design for the GPU that used dual-ported VRAM with the video DAC wired directly to the read on the RAM and the other (read/write) port connected to the GPU. This was effectively a bet that VRAM was going to become mainstream and cheap, which ended up not happening - instead, most video card manufacturers started using SGRAM instead.

As a result of this, and because the PSX was selling very well, Sony decided to redesign the GPU to use the more readily available SGRAM. While they were doing this, they also decided to remove an operational restriction that had been imposed by the original design - as I mentioned earlier, the video DAC on the original consoles was driven directly by the VRAM - which also meant that it had to operate in the same bit depth as the framebuffer did. The PSX uses a 16 bit mode (5:5:5:1 R:G:B:A) for it's 3D operations, so the shading functions also had to operate with only 5 bits of intensity.

With the new GPU, the DAC was connected directly to the pins on the GPU, so it could continue to use 8:8:8 RGB mode even when the machine was processing 3D - this allowed it to use 8 bits of intensity and hence deliver smoother shading.

I wouldn't worry about your chip - the console should be able to boot anything you put in it - the only slight issue is that in any machine later than the SCPH-700x series the chip will slightly degrade the performance of the CD drive because of the way the modchip signal needs to be injected.
 
@Trimesh
I wonder whether a series SMD capacitor on the modchip data line could improve the situation a little.
It would high pass the signal and remove any DC offset.
Do you think that'll help at all?

@helakustorm
Your consoles are already as good as a PAL machine can be.
The only possible improvement is providing NTSC timings for those games (extra NTSC console or dual oscillator installation for your PAL).
 
@Trimesh
For SCPH-5552 what modchip do you recommend between MM3 and Mayumi v4?
I ask you this because unfortunately I can't made a PsNee modchip :(
For me for the future do you have a diagram with how to install those oscillators and PsNee modchip?

Thanks!
 
US PS3 for American PS1 games (all 2 of them I still have) and Japanese PS2 for PS1 games (getting a Japanese PSone for compatibility reasons)
 
helakustorm said:
@Trimesh
For SCPH-5552 what modchip do you recommend between MM3 and Mayumi v4?
I ask you this because unfortunately I can't made a PsNee modchip :(
For me for the future do you have a diagram with how to install those oscillators and PsNee modchip?

Thanks!
Click to expand...

In this application, they are equivalent - the only difference is that Mayumi uses an extra wire for the clock and MM3 uses the internal RC oscillator on the PIC. I tend to use the MM3 simply because it's one less wire - although you have to be sure your programmer doesn't trash the oscillator calibration value, which was a bug in some of the old ones.

I did a document that described how to do a dual oscillator mod on a PU-18 machine like the SCPH-5552 - unfortunately, it's a .PDF and can't be uploaded here, but you can get it from the thread on psxdev.net:

[Hardware Mod] NTSC/PAL reference oscillator mod for PU-18 - PlayStation Development Network

www.psxdev.net www.psxdev.net

The PSnee stuff is also on psxdev:

PSNee further development - PlayStation Development Network

www.psxdev.net www.psxdev.net

@rama

I found sticking caps in the line had no noticeable effect.
 
Okay.
There should be some effect, but I suppose we have no reliable test rig / method to see it.
It doesn't help that the read performance of a particular drive assembly can be so random :p
 
Trimesh,

What do you think about the SCPH-5502?

Unfortunately I bought it believing it to be a SCPH-5552 :(

I didn't pay to much, it cost like 7.3 $.

It is good like yours?

Thanks!
 
helakustorm said:
Trimesh,

What do you think about the SCPH-5502?

Unfortunately I bought it believing it to be a SCPH-5552 :(

I didn't pay to much, it cost like 7.3 $.

It is good like yours?

Thanks!
Click to expand...

It's exactly the same machine - all that SCPH-5552 means is that it was originally supplied as part of the "Value Pack" bundle with 2 controllers and a memory card. The SCPH-5502 was the model that was supplied in the original standard retail pack with a single controller and no memory card.

I guess they changed the part number so it would match the one on the box.
 
for the past week i have been testing modchips in some of my ps1 consoles and i have learned a bit with my own experiments. i was under the impression that the MM3 was the de facto standard when it comes to modchips, in some ways it is, but ill try to explain, i was testing out cheat carts and discs in my scph-1001 that has a MM3 installed, i noticed that when i booted into the gameshark pro 3.2 cart and picked out some cheats and then went to launch game, it would just freeze. the backup would boot without the gameshark cart just fine, so i tested a gameshark cd, and it was the same result, so i then tested just booting into gameshark pro 3.2 cart and quickly chose launch game without codes and the backup would boot, i also tested leaving the lid open when picking out cheats and then closing the lid right before loading the disk, this also didn't work. i then tested out this on a few of my other ps1 revisions, scph-5501, scph-101 PsOne "used the gameshark cd only of course" they all failed with using gameshark carts or discs.

so i started looking up some info on the MM3 hex and figured out that it used the internal oscillator instead of the ps1's, and something may be up with the lid switch monitoring because when opening and closing the lid the chip should see this and start the process over, i don't have any proof but i think this is the issue with the MM3.

" i also want to take the time to say that my backups and lasers are working fine, the discs will boot just fine in all of the ps1 consoles i have used for the tests. and the laser in my scph-1001 is upgraded to a BAM"

so i started reading up on PsNee and mayumi v4, i swapped out the mm3 in my scph-1001 with a Pro Micro running the latest PsNee code and it worked 100% of the time with gameshark cart and cd, i could spend as much time as i wanted in the cheat cart or cd, pick the cheats i wanted and then launch the game, no issues. the PsNee monitors the laser and when the laser moves to the sector where the wobble code is stored on an original disk the PsNee starts to spam the wobble code, when the laser moves away from that sector the PsNee stops sending the code, it monitors the SUBQ and SQCK insted of the oscillator, its really a smart chip

i then swapped out the MM3 in my scph-101 slim with a mayumi v4, tested out the gameshark cd and it worked, i was able to use the gameshark cd without issues, the mayumi v4 uses the ps1's oscillator instead of using the PIC's internal one, pretty good results with the mayumi v4.

all of the chips mentioned can be made at home with a simple pic programmer "or a USB cable for the PsNee".

So in summary, if you are just wanting to boot backups or imports on a north american console then any of these chips will work.
if you are wanting to use cheat carts or discs, then the mayumi v4 or the PsNee is the better option.
if you want a more future proof chip that may get some added features in the future then get the PsNee
if you want to know what my pick for best modchip for ps1 is then i would say PsNee
 
I'm surprised you're seeing much difference between Mayumi4 and MM3 to be honest - from examination of the code, I'm about 99% sure that MM3 was copied from the Mayumi.
 
Trimesh said:
I'm surprised you're seeing much difference between Mayumi4 and MM3 to be honest - from examination of the code, I'm about 99% sure that MM3 was copied from the Mayumi.
Click to expand...
it may be the wiring, it may be the MM3 using the internal oscillator, but it refused to work with gamesharks, if you have a mm3 installed, try a gameshark cart or disc and see if you can pick some cheats and load a game, i have tried this on 4 playstations running mm3 and they all wouldn't boot, mayumi v4 and PsNee worked right away
 
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