This will dump the Pokemon Mini 4kb Bios (0x0-0x1000) by sending it to the PC via rs232 serial communication.
To wire your PM to your PC just open the PM and search for 2 pads labeled with TXD and RXD on the PM board close to the IR diode/receiver. Just solder a wire to the pad that is next to the IR diodes and solder this wire to pin 2 of a standard 9 pin serial connector. Then solder a wire to GND (-) of your pokemon mini battery holder and connect this wire to pin 5 of the serial connector. That’s it!
Now just flash the ROM to a flash cart, start the PC app (it only receives everything on the serial port and writes it to a file) and then turn your PM on. The transfer is just running at 1200 baud so it will take a little while after everything is transfered.
I found out that every PM Bios is the same. The Bios included in Pokemon Channel is just the same as the Bios on an EU or US Pokemon Mini.