Leapster Explorer: UART Boot
Contents
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.
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
Emerald Boot Source Found in the LF-Linux-* archive
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]
SD[6]
Example:
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.
