Nintendo Game Boy Advance ProDG
SN Systems complete development system
This system consists of
a hard-wired Game Boy Advance that would connect (via an interface
and SCSI cable) to the included SCSI card installed into a computer.
You could then load your compiled game code directly into the GBA
for testing. (The GBA appears to be a normal consumer unit with a
slight modification for power.)
This is the manual, software
and SCSI card that came with the package.
As I mentioned above, the
GBA appears to be a normal commercial unit with a wired cartridge
plugged into. Here's the inside of the cartridge itself:
The cartridge then connects
to an interface box that would then connect to the computer itself.
Here's the inside of the interface box: