Let us have a look at the Western Technologies Development Card functioning with a simple Sonic binary file. Uploaded (they call it downloading) from the PC to the Mega Drive through the PC’s parallel port, with the image held in SRAM on the development cartridge.

The comparison to a Mega EverDrive was about loading game code without burning EPROMs. The 2012 Mega EverDrive could load ROMs from SD or receive them from a PC over USB into cartridge memory. Beats having to burn the EPROMs with the game code every time you update code!

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