Leapster Explorer: UART Boot

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Revision as of 18:47, 7 November 2010 by PhilKll (talk | contribs) (Programs Needed)
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State of Affairs

UART boot looks to be working as expected now. Next step is to compile a working bootloader. Lightning-boot for the didj seems to be the most likely candidate at this moment.

Getting Started

This how-to will show you how to gain UART Boot access to your Explorer. This involves a hardware hack not for the faint of smd soldering skills, or eye sight. There is two connections that need to be made to some pads that are very very tiny, takes some soldering skills, so be prepared. Also being a hardware hack, there is there is a chance of breaking something important, be careful and be warned.

How tiny are the pads? Here is a comparison of a normal resistor vs the pads you will be soldering to.

Leapster Explorer-D6 comparison.jpg

Notice that the width of the pad is the same size as the stripe on the resistor. If you don't feel comfortable soldering something this small, this mod might not be good for you to attempt.

Programs Needed

Devroot Handy tool for setting up Codesourcery to build Emerald Boot

Micromon Used to send EB over UART and executing it

Software Needed

A UART enabled Emerald-Boot.bin/Lightning-Boot.bin (work in progress)

Hardware

DJHI or similar cartridge for access to UART console

Soldering Iron (with very tiny tip)

Wire (very fine gauge)

2x 10K Ohm Resistor

2x Switch or jumper pins

On Explorer

Pictures SD[13] and SD[6] show the pads you will be working with. Take your 4 pieces of wire and strip a small amount of insulation off one end of each, and solder one to each pad shown, watch your heat and where the tip is, so as not to destroy the pad or unsolder the component next to it. A magnifier would be a good idea here. Then on one of the wires, of the two to be connected together, attach the resistor and on the other the switch, then solder the resistor to the switch. Add a dab of hot glue or some other means of strain relief, put back together and you are done. To test, hold down both buttons, while you turn on your Explorer, nothing should happen. Try it with out holding down the buttons, to verify your Explorer still works.


SD[13] LX SD13 UART Enable.jpg

SD[6] Leapster Explorer-D6 Pull Down.png


Example:

D6hack.jpg

Bootloader

Doesn't exist yet, requires modifications to a current boot loader that are yet to be figured out.

Didj examples of UART Booting, should be nearly the same.

UART Boot Didj with Linux

UART Boot Didj with Windows

Under Windows

Under Linux