Difference between revisions of "NEO-MGA"

From NeoGeo Development Wiki
Jump to: navigation, search
m (1 revision)
m
(12 intermediate revisions by the same user not shown)
Line 1: Line 1:
[[File:cd2_mga.jpg|right|thumb|NEO-MGA-T chip found on a CDM3-2 board.]]
+
{{ChipInfo
 +
|picture=cd1_neo-mga.jpg
 +
|pkg=QFP160
 +
|manu=fujitsu
 +
|date=1994 ?
 +
|gates=?
 +
|used_on={{PCB|CDROM-2 board|CDROM-2}}, {{PCB|MV1A}}...
 +
}}
  
The NEO-MGA-T is a damn chip nobody knows about, which is found in the CD1 and CD2 versions of the NeoGeo hardware.
+
Multi-purpose chip found in CD systems and some late MVS boards:
The CD-Z has a NEO-MGA-T2, probably to handle the faster CD reading speeds and new copy protection system.
+
* NEO-MGA in the CD1 model (front loading).
The front loading NeoGeo CD has a NEO-MGA chip.
+
* {{Chipname|NEO-MGA-T}} in the CD2 model (top loading) and {{PCB|MV1A}} MVS boards, can be swapped with NEO-MGA.
 +
* {{Chipname|NEO-MGA2-SA}} in the [[CDZ]], replaces the {{Chipname|LC8953}} ?
  
It's in charge of the communication with the CD drive, data transfers to the [[LC89515]] host and buffering CDDA data for the [[BIOSes]] vu-meters.
+
It is used for address decoding, communication with the [[CD drive]], for refreshing {{Chipname|68k}} [[DRAM]], and for buffering serial [[CDDA]] data.
  
[[Catégorie:Chips]]
+
=CD pinout=
 +
 
 +
[[File:Neo-mga_CD_pinout.png|700px]]
 +
 
 +
[[File:Neo-mga_cd.odg]]
 +
 
 +
=MV1A pinout=
 +
 
 +
[[File:Neo-mga_MV1A_pinout.png|700px]]
 +
 
 +
[[File:Neo-mga_mv1a.odg]]
 +
 
 +
=Signals=
 +
 
 +
* DRM*, RAS, CAS, WRITE: See TC514400 DRAM datasheet.
 +
* X*: See [[LC8953]] datasheet.
 +
 
 +
[[Category:Chips]]

Revision as of 15:12, 1 August 2022

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

Multi-purpose chip 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, can be swapped with NEO-MGA.
  • NEO-MGA2-SA in the CDZ, replaces the LC8953 ?

It is used for address decoding, communication with the CD drive, for refreshing 68k DRAM, and for buffering serial CDDA data.

CD pinout

Neo-mga CD pinout.png

File:Neo-mga cd.odg

MV1A pinout

Neo-mga MV1A pinout.png

File:Neo-mga mv1a.odg

Signals

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