Spime

Short for the SPI Memory Emulator.

This is User:Scanlime's approach to bootstrapping code via savegame hacks and providing a debug channel back to the PC. Whereas EEPUART is a serial port, spime is a shared memory buffer.

It is implemented on a Xilinx Spartan 3 FPGA board in Verilog. A 1MB SRAM buffer is concurrently accessible by the PC over a 3 MBit serial port, and by the DS over an SPI EEPROM emulator. This buffer can store normal save files, plus it can be used as a fast communication channel for memory dumps, commands to execute, etc.

This shared memory buffer can also be used to send simple RPC-like commands to the DSi, implementing a very simple debug monitor for poking at registers in real-time.

Source code is under a BSD-style license, available from a public Subversion repository.