Jump to content

Photo

TI 99/4a to an RGB arcade monitor?


6 replies to this topic

#1 Tornadoboy OFFLINE  

Tornadoboy

    Space Invader

  • 31 posts

Posted Sun Feb 5, 2017 10:47 AM

Just curious, is there a way to get RGB out of the 99/4a mother board that's compatible with standard arcade game monitors? If not I think I could probably just use a Dragon's Lair NTSC-RGB board but I'm not 100% sure on that either.

 

I'm probably not going to work on it anytime soon, but I've had fantasies of making a "Tex-Flex" arcade system like Exidy once did for the Atari 600 with their "Max-A-Flex" system. For those unfamiliar with it:

 

http://www.classicar.../Max-A-Flex.htm


Edited by Tornadoboy, Sun Feb 5, 2017 11:00 AM.


#2 arcadeshopper OFFLINE  

arcadeshopper

    River Patroller

  • 2,132 posts
  • Location:Portland, Oregon USA

Posted Sun Feb 5, 2017 12:36 PM

- the 9918a puts out composite not rgb

- you'd need a composite ntsc (with loose requirements as our TI doesn't put out super quality composite signal) to rgb like that board you mentioned which is getting rare

 

Greg



#3 fabrice montupet OFFLINE  

fabrice montupet

    Chopper Commander

  • 178 posts
  • Location:Burgundy - France

Posted Sun Feb 5, 2017 2:42 PM

You also can buy an European TI-99/4A and the PHA2037 interface. Sure, the RGB picture quality is great :-)



#4 bpatte02 OFFLINE  

bpatte02

    Chopper Commander

  • 103 posts

Posted Tue Feb 7, 2017 10:54 AM

Interesting concept. I saw a group of guys who took a raspberry pi and stepped the hdmi to VGA and then found a converter that stepped the VGA signal down to the RGB. If you had a modified TI-99/4A with VGA perhaps a step down like the GSB-8100 that these guys used might work. Or maybe a composite to VGA converter that is connected to a GSB-8100 might work. I'll be honest I'm not anywhere near being an expert, more like an avid idiot who likes to throw things at the wall and see what sticks but perhaps this article might be interesting for everyone here.

http://celso.io/2012...de-monitor.html

#5 Tornadoboy OFFLINE  

Tornadoboy

    Space Invader

  • Topic Starter
  • 31 posts

Posted Tue Feb 7, 2017 8:11 PM

There are a number of different NTSC-RGB converters out there not just from Dragon's Lair but several gambling games that used laser discs and are cheaper/easier to find, I might try one of them, and there's also a few schematics for making one from scratch that's always an option. 


Edited by Tornadoboy, Tue Feb 7, 2017 8:13 PM.


#6 fabrice montupet OFFLINE  

fabrice montupet

    Chopper Commander

  • 178 posts
  • Location:Burgundy - France

Posted Wed Feb 8, 2017 6:25 AM

Composite NTSC to RGB converters give poor results.



#7 Tornadoboy OFFLINE  

Tornadoboy

    Space Invader

  • Topic Starter
  • 31 posts

Posted Wed Feb 8, 2017 11:55 AM

I do have an F18 chip, but don't you need to tweak the VGA output like the frequency in order to get it to convert it to RGB? The TI obviously doesn't have any settings for that. 


Edited by Tornadoboy, Wed Feb 8, 2017 11:56 AM.





0 user(s) are browsing this forum

0 members, 0 guests, 0 anonymous users