Forums

Sega Master System / Mark III / Game Gear
SG-1000 / SC-3000 / SF-7000 / OMV
Home - Forums - Games - Scans - Maps - Cheats - Credits
Music - Videos - Development - Hacks - Translations - Homebrew

View topic - GG vdp in master system

Reply to topic
Author Message
  • Joined: 05 Nov 2014
  • Posts: 324
  • Location: Auckland - NZ
Reply with quote
GG vdp in master system
Post Posted: Fri Apr 10, 2020 7:02 am
Just had a bit of a thought but not sure if it would work in practice. Would it be possible to take the vdp and vram from a 2 asic game gear and transplant that into a master system? Had a quick look at the VA0 schematic and it looks doable in terms of required pins. Obviously the sound and video outputs are going to be different. A GGTV board should sort the video out. Not sure about the sound.. there appears to be 4 output pins involved with that, but would imagine its not too difficult to sort out. Im not sure how the vdp knows which mode to operate in (gg vs sms) as that seems to be fed into the other asic but there are some pins between the two that may be used for that. Has this been tried before or can any one see why it might not work?
  View user's profile Send private message
  • Site Admin
  • Joined: 19 Oct 1999
  • Posts: 13231
  • Location: London
Reply with quote
Post Posted: Fri Apr 10, 2020 8:02 am
I guess it depends what is in which chip, I don’t think we’ve given it much thought. If it is doing the VDP + VRAM + LCD driver then it seems plausible. It might take some unknown funky signals from the other ASIC though.
  View user's profile Send private message Visit poster's website
  • Joined: 05 Nov 2014
  • Posts: 324
  • Location: Auckland - NZ
Reply with quote
Post Posted: Fri Apr 10, 2020 8:12 am
On the diagram i found it seems to be separate z80 + external ram, vdp in one asic + external vram then IO + lcd driver + sound related in the second asic.

  View user's profile Send private message
  • Joined: 05 Sep 2013
  • Posts: 2686
Reply with quote
Post Posted: Fri Apr 10, 2020 10:33 am
well, you might do a 'consolized' Game Gear and add a port for SMS games...
  View user's profile Send private message Visit poster's website
  • Joined: 05 Nov 2014
  • Posts: 324
  • Location: Auckland - NZ
Reply with quote
Post Posted: Fri Apr 10, 2020 10:53 am
sverx wrote
well, you might do a 'consolized' Game Gear and add a port for SMS games...


There is that.. but theres no TH pin on port 1 so controller support becomes limited. Hacking in an sms io chip might be doable as well tho
  View user's profile Send private message
  • Joined: 05 Jan 2006
  • Posts: 311
  • Location: USA
Reply with quote
Post Posted: Mon May 04, 2020 3:41 pm
wasup wrote
sverx wrote
well, you might do a 'consolized' Game Gear and add a port for SMS games...


There is that.. but theres no TH pin on port 1 so controller support becomes limited. Hacking in an sms io chip might be doable as well tho


Lookup "neto"s posts on here. EDIT, see here:
https://www.smspower.org/forums/16031-GameGearLightPhaserAndSoftReset#98444

Neto is an 8 bit Sega god much like yourself, who developed an add on circuit like your 3D board that adds TH pins to both ports :)

I think you can do absolutely everything with a consolized GG...only 2 games need patching for FM but I think thats it (if you use available circuits).
  View user's profile Send private message Visit poster's website
Reply to topic



Back to the top of this page

Back to SMS Power!