NEO-MGA

NEO-MGA is a custom chip apparently noone knows (and wants to know) about, which is found in 3 versions in CD systems and some late MVS boards:

• NEO-MGA in the CD1 model (front loading).
• NEO-MGA-T in the CD2 model (top loading) and MV1A MVS boards. Probably the same but made by Toshiba.
• NEO-MGA-T2 in the CDZ, probably with a different pinout and maybe stuff related to the copy protection system.

It's used for communication between the main board and the CD module, for handling DRAM access (?), address decoding (?) and for buffering CDDA data.

• NEO-MGA chip found in a CD1 system.

  NEO-MGA chip found in a CD1 system.

• 

  NEO-MGA-T chip found in a CD2 system.

Pinout

File:Neo-mga.png

Pinout (NEO-MGA-T)

1,10,15,16,18,30,41,50,59,70,81,90,110,121,130,139,150: Ground.