Sony Reader PRS-T1 Hack

The install process is pretty simple. I feel comfortable in suggesting that you try it and it looks relatively foolproof.

1. Download and unzip the hack from here. Look for one that says “package installer”; that’s what you’ll need in order to install apps.
2. Plug your T1 into your PC and put it in USB mode.
3. Find the folder for the hack and double click on flash_reader.bat. Read the prompts on the screen and respond.
4. Let the T1 sit until the software finishes installing. If successful, your T1 will reboot.

If it doesn’t work, you can ask for help here. BTW, if you have already hacked the T1 then you might need to install the restore firmware first. That will remove any remaining parts of the hack. If you don’t install the restore then the broken parts might hang around.

Source:

http://www.the-digital-reader.com/2011/10/23/sony-reader-hacked-now-runs-kindle-ezpdf-and-more-video/

http://translate.google.com/translate?hl=en&rurl=translate.google.com&sl=ru&u=http://www.the-ebook.org/forum/viewtopic.php%3Ft%3D21458

 Downgrade firmware

I followed the procedure described in this post and successfully downgraded from 1.0.07 to 1.0.05. You need to know a little bit of linux to know what to do if things don't go exactly as written. Let me quickly summarize what you need to do.

1. Flash restore-set to force the system to have v1.0.05. This is necessary because the rupore-rescue works on v1.0.05. The firmware will continue to read v1.0.07.

2. The rupore-rescue zip has two items; a folder "OS firmware" and a file called gserial.inf. Copy the "OS firmware" folder in the rupore-rescue zip to the root of your external SD card.

3. Turn off the device and boot into recovery mode (hold back and home buttons while the device is being turned on). The device wont be recognized. Go to device drivers, look for the device and use the gserial.inf as the driver file. Take note of the port number of the device (something like com18 or whatever). The device will now be recognized and you will be asked by windows whether you'd like to format the disk. Say no.

4. Open putty, change to serial, put in the port number and log into the device.

5. Type root and you now have root access to the device.

6. Mount the sdcard : mount -t vfat /dev/mmcblk0p1 /initrd/mnt/sd

7. Make a backup image of the internal storage (about 1.8GB) on the sd-card (takes about 10 minutes) : dd if=/dev/mmcblk2 of=/initrd/mnt/sd/mmcblk2.img

8. Take out the sdcard, put it in your phone or something else and copy the file mmcblk2.img to your computer.

9. Use a hex editor (I have editpad pro) and replace all instances of 1.0.07.05070 with 1.0.03.11140 (there are 3 of them). Save.

10. Copy the file back into your sdcard, insert into the reader.

11. Reboot the device back into recovery just to make sure that the reader has read the sdcard.

12. Now, restore the modified image : dd if=/initrd/mnt/sd/mmcblk2.img of=/dev/mmcblk2

13. Reboot the device (not recovery).

14. Run the 1.0.05 installer and you're done.  

https://www.mobileread.com/forums/showthread.php?t=276109

sony reader PST1 packages
https://projects.mobileread.com/reader/users/porkupan/PRST1/flash_packages/