# ONEchip modchip installation guide \- William Quade

Canonical: <https://quade.co/ps1-modchip-guide/onechip/>
Language: `en-US`

![ONEchip modchip](https://quade.co/wp-content/uploads/2019/02/b.jpg)

ONEchip modchips were designed specifically for PAL PSone slim consoles\. They patch the additional region locking in the BIOS of these systems\. They can be made using PIC12C508A, and other PIC12 chips\. This guide covers everything you need to know about choosing, programming, and installing a ONEchip into your PlayStation\.

# Guide structure

This guide is structured into several pages\. It’s organized like this primarily so that comments can be more organized and useful for readers\.

This page covers the ONEchip modchip\. It includes general information about the chip, and then links off to installation guides for each console model\.

If you want more information about PlayStation 1 modchips in general [check out this guide](https://quade.co/ps1-modchip-guide/) \.

# ONEchip modchip installation diagrams

[![ONEchip modchip](https://quade.co/wp-content/uploads/2019/02/b-1024x768.jpg)](https://quade.co/wp-content/uploads/2019/02/b.jpg)

Below is a list of all PlayStation 1 motherboard versions \(at least the ones that are compatible with ONEchip\), along with the console model numbers associated with them\. You can get a good idea of what board you have by looking at the model number underneath your system \(something like SCPH\-102\)\.

To actually know what board you have you’ll most likely have to open up your console and look for the board version printed somewhere on the board \(something like PM\-41 \(2\) or PM\-41\)\.

Once you know what board you have you can click on the board model and you’ll be sent to a page with the installation diagram\.

- [PM\-41](https://quade.co/ps1-modchip-guide/onechip/pm-41/)
- Earlier SCPH\-102, and SCPH\-103’s
- [PM\-41 \(2\)](https://quade.co/ps1-modchip-guide/onechip/pm-41-2/)
- Later SCPH\-102, and SCPH\-103’s

# ONEchip modchip drawbacks

The biggest problem with ONEchip chips is that they are only compatible with PAL PSone consoles\.

They also base their timing on the internal oscillator within the PIC chips\. Using the internal oscillator can sometimes cause the chip to become out of sync with the console when booting, meaning you’ll have to restart the console to boot\.

Certain PIC programmers can also mess up the internal oscillator value when programming, which could be a problem if you are programming your own chips\. Additionally it has been reported that certain batches of PIC chips have had problems with the oscillator value in the past\.

# ONEchip modchip advantages

The biggest advantage of the ONEchip is that they are one of the only chips that allows you to play non\-PAL games on a PAL PSone\. The other compatible chip is the ATmega based PsNee chip\.

# ONEchip modchip source code

If you’d like to program your own ONEchip modchips you’ll need the source code\. Right now I only have the code for the PIC12C508A\.

- [PIC12C508A](https://drive.google.com/file/d/1FIyK_qiWjC__SUk7x94MDwitplEbKAR9/view?usp=drive_link)

I’ll have a tutorial on how to program these PIC chips in the future\.

16 Comments

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![Jimmy](https://secure.gravatar.com/avatar/d8ccda0e2c4b678b74d9b4121662c6c05b6421f60c269517e47f0d6c82b246de?s=64&d=mm&r=g)

Jimmy

January 27, 2021 5:53 PM

Just programmed this hex to a 12C509A, works perfect

4

![VajskiDs](https://secure.gravatar.com/avatar/1fc3e6eb24e5df4ee7985555b79ffab0363600b7f8884a8366da7bd774f3a3c3?s=64&d=mm&r=g)

VajskiDs

August 20, 2021 11:12 AM

[https://github\.com/L10N37/tehUberChip\_Another\_PSX\_Modchip/blob/main/PIC12F675/Uber\-D\-D\_PM41\_PAL\.ASM](https://github.com/L10N37/tehUberChip_Another_PSX_Modchip/blob/main/PIC12F675/Uber-D-D_PM41_PAL.ASM)

I have a new modchip for this version
 it’s quite reliable, seems to pick up the injection strings a lot quicker on some games on this ASM version \(as oppose to the arduino one\)

I’d be more than happy for you to stock these and sell with just a mention of “vajskids consoles’
 Cheers
 Btw: I recommended you on a social media platform for a US buyer for premodded system

4

![Ivan Timofeev](https://secure.gravatar.com/avatar/3848927cd1aaa1cab0549e45d1cf69aadef2fee12d23079c458857df4394d615?s=64&d=mm&r=g)

Ivan Timofeev

February 21, 2019 2:29 AM

We are waiting for the firmware\.

0

[![William Quade](https://secure.gravatar.com/avatar/14ac9361c0296cbe4c2282fc8bdbd92bd0f1f946ca84939cc222c68e865637e5?s=64&d=mm&r=g)](https://quade.co/)

Author

[William Quade](https://quade.co/)

February 21, 2019 8:41 AM

Reply to [Ivan Timofeev](#comment-2132)

I added the hex file\.

0

![Tom](https://secure.gravatar.com/avatar/109e98ea875e65590c0051798918ce540b962f741ed21933a29b470c2907640f?s=64&d=mm&r=g)

Tom

January 1, 2020 6:41 PM

Reply to [William Quade](#comment-2133)

Was this ever ported over to the 12f629 chips?

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[![William Quade](https://secure.gravatar.com/avatar/14ac9361c0296cbe4c2282fc8bdbd92bd0f1f946ca84939cc222c68e865637e5?s=64&d=mm&r=g)](https://quade.co/)

Author

[William Quade](https://quade.co/)

January 1, 2020 6:43 PM

Reply to [Tom](#comment-2560)

I don’t think so\.

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![William](https://secure.gravatar.com/avatar/ebd6aab2face312a86751396deb83c2b5c833c54536251a4a1ef74e92808ff9a?s=64&d=mm&r=g)

William

January 8, 2020 4:31 AM

So this is the chip I’d need for my PAL Australian scph 102?

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[![William Quade](https://secure.gravatar.com/avatar/14ac9361c0296cbe4c2282fc8bdbd92bd0f1f946ca84939cc222c68e865637e5?s=64&d=mm&r=g)](https://quade.co/)

Author

[William Quade](https://quade.co/)

January 9, 2020 6:16 AM

Reply to [William](#comment-2574)

Yes\.

0

![Robert](https://secure.gravatar.com/avatar/897aac72d70862f6ac057937e987c7055c01489d627e636b93b227da826eda47?s=64&d=mm&r=g)

Robert

December 11, 2020 12:44 AM

One chip hex here is for europe?

0

[![William Quade](https://secure.gravatar.com/avatar/14ac9361c0296cbe4c2282fc8bdbd92bd0f1f946ca84939cc222c68e865637e5?s=64&d=mm&r=g)](https://quade.co/)

Author

[William Quade](https://quade.co/)

December 15, 2020 2:47 PM

Reply to [Robert](#comment-4676)

OneChip is only for PAL PSone SCPH\-102 slim consoles, no other models\.

1

![Robert](https://secure.gravatar.com/avatar/897aac72d70862f6ac057937e987c7055c01489d627e636b93b227da826eda47?s=64&d=mm&r=g)

Robert

December 19, 2020 7:17 PM

Reply to [William Quade](#comment-4681)

Nice, I just programmed your hex file for one chip on the pic 12c508a, time to install it on scph\-102 \(pm\-41/2\) 😁
 Thanks for letting me know more about the electronics 👍👌

0

![Jamie](https://secure.gravatar.com/avatar/d8ccda0e2c4b678b74d9b4121662c6c05b6421f60c269517e47f0d6c82b246de?s=64&d=mm&r=g)

Jamie

February 23, 2021 2:46 PM

Trying to program this to a 12f508 but keep getting ‘out of address of device’ error, does anyone know how to fix this? I’m using the tl866 ii plus and xgpro software, thanks

0

[![William Quade](https://secure.gravatar.com/avatar/14ac9361c0296cbe4c2282fc8bdbd92bd0f1f946ca84939cc222c68e865637e5?s=64&d=mm&r=g)](https://quade.co/)

Author

[William Quade](https://quade.co/)

February 24, 2021 8:54 AM

Reply to [Jamie](#comment-4812)

Whatever hex file you are using is probably for the 12C508A and not the 12F508 so they don’t quite line up\.

0

![Jamie](https://secure.gravatar.com/avatar/d8ccda0e2c4b678b74d9b4121662c6c05b6421f60c269517e47f0d6c82b246de?s=64&d=mm&r=g)

Jamie

February 24, 2021 12:05 PM

Reply to [William Quade](#comment-4814)

Ah ok, I had read that they were practically identical so assumed the same hex worked on both chips, could you point me to a hex that works with the 12f508 please?

Last edited 5 years ago by Jamie

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[![William Quade](https://secure.gravatar.com/avatar/14ac9361c0296cbe4c2282fc8bdbd92bd0f1f946ca84939cc222c68e865637e5?s=64&d=mm&r=g)](https://quade.co/)

Author

[William Quade](https://quade.co/)

February 24, 2021 12:37 PM

Reply to [Jamie](#comment-4819)

You can probably just flash the same hex if you make sure all of the fuses are correct\.

0

![Jamie](https://secure.gravatar.com/avatar/d8ccda0e2c4b678b74d9b4121662c6c05b6421f60c269517e47f0d6c82b246de?s=64&d=mm&r=g)

Jamie

March 2, 2021 5:14 PM

Reply to [William Quade](#comment-4821)

Found the issue, the software was missing the last address line when 12f508 selected, I programmed it under 12c508 and manually entered the oscillator value and it works now

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