NEO-MGA: Difference between revisions

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|date=1994 ?
|date=1994 ?
|gates=?
|gates=?
|used_on={{PCB|CDROM-2 board|CDROM-2}}, {{PCB|MV-1A}}...
|used_on={{PCB|CDROM-2 board|CDROM-2}}, {{PCB|MV1A}}...
}}
}}


NEO-MGA is a custom chip apparently noone knows about, which is found in 3 versions in CD systems and some late MVS boards:
NEO-MGA is a custom chip apparently noone knows 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 in the CD1 model (front loading).
* {{Chipname|NEO-MGA-T}} in the CD2 model (top loading) and {{PCB|MV-1A}} MVS boards. Probably the same but made by Toshiba.
* {{Chipname|NEO-MGA-T}} in the CD2 model (top loading) and {{PCB|MV1A}} MVS boards. Probably the same but made by Toshiba.
* {{Chipname|NEO-MGA-T2}} in the [[CDZ]], probably with a different pinout and maybe stuff related to the [[copy protection]] system.
* {{Chipname|NEO-MGA-T2}} in the [[CDZ]], probably with a different pinout and maybe stuff related to the [[copy protection]] system.


It is used for communication between the main board and the [[CD modules|CD module]], for handling [[DRAM]] access (?), address decoding (?) and for buffering [[CDDA]] data.
It is used for communication between the main board and the [[CD drive]], for handling [[DRAM]] access (?), address decoding (?) and for buffering [[CDDA]] data.


=Pinout=
=Pinout=

Revision as of 00:05, 21 February 2017

File:Cd1 neo-mga.jpg
Package QFP160
Manufacturer
First use 1994 ?
Used on CDROM-2 board, MV1A...

NEO-MGA is a custom chip apparently noone knows 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 is used for communication between the main board and the CD drive, for handling DRAM access (?), address decoding (?) and for buffering CDDA data.

Pinout

File:Neo-mga.png

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

Signals