Difference between revisions of "Didj"

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(Boot Loader)
(Tutorials/How To's)
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* [[Didj_and_Explorer:_boot_pixel_format|Changing the fb driver to display the boot logo correctly]]
* [[Didj_and_Explorer:_boot_pixel_format|Changing the fb driver to display the boot logo correctly]]
* [[LeapFrog_Pollux_Platform:_TV_Out | TV Out]]
* [[LeapFrog_Pollux_Platform:_TV_Out | TV Out]]
* [[Didj_2.6.31_Generic_Buildroot | Generic Buildroot Rootfs and Kernel build]]
''' Games and Emulators '''
''' Games and Emulators '''

Latest revision as of 23:08, 25 February 2013

This device is part of the LeapFrog Pollux Platform, it's recommended to start there for general information.

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 It has been replaced by the Leapster Explorer.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.

Boot Loader

Sources and Toolchains

Tutorials/How To's



USB Storage


Flash NAND

Firmware Image


Games and Emulators

Brio Development


Compiling Source Code

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

Active Kernel/Rootfs

Near the begging of the boot message you should see one of two root options:


You are using mtd4: 00e00000 00020000 "Linux_RFS0" or


You are using mtd6: 00e00000 00020000 "Linux_RFS1"


Name Location Size Device Notes
LF1000_uniboot 0x00000000 0x00020000 /dev/mtd0 Lightning Boot
Atomic_Boot_Flags 0x00020000 0x000E0000 /dev/mtd1 On NAND
Manufacturing_Data 0x00100000 0x00100000 /dev/mtd2 On NAND
Kernel0 0x00200000 0x00200000 /dev/mtd3 On NAND
Linux_RFS0 0x00400000 0x00E00000 /dev/mtd4 On NAND
Kernel1 0x01200000 0x00200000 /dev/mtd5 On NAND
Linux_RFS1 0x01400000 0x00E00000 /dev/mtd6 On NAND
Brio 0x02200000 0x0DE00000 /dev/mtd7 On NAND
EXT 0x10000000 0x10000000 /dev/mtd8
Cartridge 0x00000000 0x10000000 On Cartridge NAND

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