# Chronoswitch

> Using Chronoswitch to downgrade or reinstall official PSP firmware.

# Chronoswitch

Chronoswitch is a tool that lets you install or reinstall official PSP firmware. It is useful in the following scenarios:

- Reverting to an older firmware (e.g. 6.61 to 6.60)
- Removing Infinity and/or custom firmware to revert to stock
- Removing Infinity v1 to install Infinity v2
- Removing custom firmware to install ARK-5

## Before you start

There are always risks when modifying firmware. Reduce them by:

- Having at least **80% battery life**
- Making sure your battery cannot fall out during the process
- Keeping the charger plugged in

## Downloads

- [Chronoswitch](https://www.pspunk.com/psp-chronoswitch/)
- Firmware files: [6.60 and 6.61](https://www.pspunk.com/psp-update/) or [other versions](https://darthsternie.net/psp-firmwares/)

Do not downgrade to firmware below **6.20**. This guide has been tested with 6.60 and 6.61.

## Steps

**1. Download the correct firmware file**

Download the firmware version you want to install. The **PSP Go** uses a different update file than all other PSP models. Make sure you get the right one for your model.

If your file is not named `EBOOT.PBP`, rename it to `EBOOT.PBP`.

**2. Transfer the firmware file**

Transfer the firmware file to your memory stick at the following path:

```
PSP/GAME/UPDATE/EBOOT.PBP
```

PSP Go users can place the file on internal storage or the memory card.

**3. Transfer Chronoswitch**

Download `Chronoswitch.zip`, extract it, and copy its `EBOOT.PBP` to:

```
PSP/GAME/Chronoswitch/EBOOT.PBP
```

Create the `Chronoswitch` folder if it does not exist.

**4. Run Chronoswitch**

Disconnect from USB mode. In the **Game** tab on the XMB you will see both the Chronoswitch application and an entry for the firmware version you are installing. Open **Chronoswitch** and follow the on-screen instructions, pressing **X** to continue.

The PSP will load the official firmware installer. Follow the steps on screen. Once complete, the PSP will restart on the firmware version you chose.

## Credits

DaveeFTW, Krazynez, TheZett, Darth Sternie, some1, bbtgp, coyotebean, kgsws, Silverspring, Bubbletune, qwikrazor87