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We are currently in the process of upgraded and organizing these pages, please forgive the mess, thank you.

The LeapFrog Didj


The Didj was a toy produced by Leapfrog marketed for educational games for children aged 5-10.

Didj was end-of-lifed by Leapfrog in mid-2010. It has been replaced by the Leapster Explorer.

Although Didj has a proprietary graphical front end, it runs a generic Linux distribution on an Arm based processor. Soon after the Didj's release, it was discovered that the cartridge port contained pins that allowed for serial console access with root privileges. After this discovery, work began to modify the Didj into an accessible emulation device.

Since development began, much has been accomplished, including:

  • Discovered that the Arm chip is the same as on the GP2X Wiz, only at a lower clock speed.
  • Created cartridges that support SD cards
  • Accessed the UART features in the cartridge slot


LeapFrog Pollux Platform

The Didj is part of 3 different devices that all share a common hardware platform, based around the Pollux SoC. The platform page contains information generic across these devices, and it is recommended that you refer to that page as it is a good starting point to understanding the Didj, and contains some basic How To's and Tutorials to get you started.

Tutorials/How To's

clean up note: Finished


Boot Loader

clean up note: Not Finished

2.6.31 Kernel LF-Linux-2503-20110602-1237 Firmware Version

Depreciated, for LF-Linux-8291-20101026-1425 Firmware Version

Flashing the Didj

On Didj


Development Scripts and Programs

Technical Information


File System Info

  • rootfs / rootfs rw
  • /dev/root / jffs2 ro
  • none /proc proc rw
  • sysfs /sys sysfs rw
  • /dev/ram0 /tmp tmpfs rw
  • /dev/mtdblock1 /flags jffs2 rw,sync,noatime
  • /dev/mtdblock2 /mfgdata jffs2 ro,sync,noatime
  • /dev/mtdblock10 /Didj vfat rw,noatime,fmask=0022,dmask=0022,codepage=cp437,iocha rset=iso8859-1
  • /dev/mtdblock11 /Cart vfat ro,noatime,fmask=0022,dmask=0022,codepage=cp437,iocha rset=iso8859-1
Filesystem                Size       Mounted on
/dev/mtdblock6           14.0M     /
/dev/mtdblock1          896.0k    /flags
/dev/mtdblock2            1.0M    /mfgdata
/dev/mtdblock9          215.8M    /Didj

if at boot you see:


you are using mtd4: 00e00000 00020000 "Linux_RFS0"


you are using mtd6: 00e00000 00020000 "Linux_RFS1"

Batteries and Recharging Station

Battery Compartments

The Didj has two identical battery compartments, the combined collection of batteries are wired in series.

  • Battery Compartment Terminals:
    • Term 1 - Battery +
    • Term 2 - Temp Sensor + Wired to Pollux pins K20 / GPIOA 28 and K21 / GPIOA 29
    • Term 3 - Temp Sensor -
    • Term 4 - Battery -

Rechargeable Batteries

In addition to the terminals facing the Didj's contacts, there are another set of contacts facing away from the Didj. These contacts are duplicates used by the charging station. The batteries themselves are NIMH cells, producing around 2.5v per pack when fully charged.

Recharging Station

The recharger station contains a battery charge circuit with temperature monitoring. The station also has a pair of contacts that duplicate the 9V dc barrel jack.

SSP / SPI Controller

Didj SPI Info


External Links