Difference between revisions of "NEO-MGA"

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NEO-MGA is a custom chip apparently noone knows about, which is found in 3 versions in CD systems and some late MVS boards:
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NEO-MGA is found 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|MV1A}} 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 drive]], for handling [[DRAM]] access (?), address decoding (?) and for buffering [[CDDA]] data.
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It is used for communication with the [[CD drive]], for handling {{Chipname|68k}} program and work [[DRAM]] access, some address decoding and for buffering serial [[CDDA]] data.
  
 
=Pinout=
 
=Pinout=
  
[[File:Neo-mga.png]]
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[[File:Neo-mga.png|700px]]
  
1,10,15,16,18,30,41,50,59,70,81,90,110,121,130,139,150: Ground.
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[[File:Neo-mga.odg]]
  
 
=Signals=
 
=Signals=
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* DRM*, RAS, CAS, WRITE: See TC514400 DRAM datasheet.
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* X*: See [[LC8953]] datasheet.
  
 
[[Category:Chips]]
 
[[Category:Chips]]

Revision as of 21:47, 5 March 2017

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

NEO-MGA is found 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 with the CD drive, for handling 68k program and work DRAM access, some address decoding and for buffering serial CDDA data.

Pinout

700px

File:Neo-mga.odg

Signals

  • DRM*, RAS, CAS, WRITE: See TC514400 DRAM datasheet.
  • X*: See LC8953 datasheet.