Help with Minor R-Type graphics issues

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    • Help with Minor R-Type graphics issues

      Well I believe this to be minor... :P

      Anyway, there are what appears to be vertical bars affecting only some background graphics.

      In the screens attached you can see it affects the Warning text screen, Ram check and title screen (not shown). In the other screen shot you can see that during game play the bars knock out parts of the stage graphics as it scrolls however no sprites are effected when they pass over it.

      Some basic things I have tried:
      • Re-seated daughter board
      • re-seated all EPROM's
      • piggy backed a number of the worker RAM's
      • one at a time removed some of the EPROM's while running to see if they effected the issue. No luck..


      Planning to do more on this soon, dump and check EPROM's etc.. but I am mainly posting this to see if anyone else has come across the issue before and can narrow down my area of investigation..

      Thanks.
      Images
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    • Faulty custom chip on the bottom board?
      Don't panic, @caius has reproduced them.

      Or maybe RAM issue.
      Looking for:
      - faulty Space Harrier or Enduro Racer
      - Sega Mega-CD 1 power board
      - Super Nintendo CPU (3 needed)



      "I'd 1cc games but I have a real life."
      01010011 01000101 01000011 01010010 01000101 01010100 00100000 01001101 01000101 01001110 01010101 00100000 01000111 01010101 01011001
    • I'm no expert, but I would think if it was RAM you would still get sprights they would just be garbled/wrong.
      The fact the sprights are missing at repeating locations seems like failing custom.
      Darksoft/Apocalypse: CPS2, CPS3, F3-β, MVS, S16-β
      RGB: RECO v2
      invzim: Jammafier v1.6b, Tri-Sync Helper
      XianXi: JNX Raiden, SC Taito Classic, SC Sega System 16/24, Namco System 11/12 KHA
      Frank_fjs: JAMMA Extender SE-HAS, Jassifier v1.6
    • Apocalypse wrote:

      Faulty custom chip on the bottom board?
      Don't panic, @caius has reproduced them.

      Or maybe RAM issue.
      Yeah ok cool.

      The other obvious thing I haven't tried yet is swapping the bottom board with another working R-Type PCB set. I will do that and see what happens.. If its not RAM on the bottom board the likely a custom I suppose.

      Thanks
    • jassin000 wrote:

      I'm no expert, but I would think if it was RAM you would still get sprights they would just be garbled/wrong.
      The fact the sprights are missing at repeating locations seems like failing custom.

      -Ace- wrote:

      Check the voltages. I had sprite issues until I bumped up the +5 voltage.
      From what I read sprites are NOT affected, only background.
      Looking for:
      - faulty Space Harrier or Enduro Racer
      - Sega Mega-CD 1 power board
      - Super Nintendo CPU (3 needed)



      "I'd 1cc games but I have a real life."
      01010011 01000101 01000011 01010010 01000101 01010100 00100000 01001101 01000101 01001110 01010101 00100000 01000111 01010101 01011001
    • Apocalypse wrote:

      jassin000 wrote:

      I'm no expert, but I would think if it was RAM you would still get sprights they would just be garbled/wrong.
      The fact the sprights are missing at repeating locations seems like failing custom.

      -Ace- wrote:

      Check the voltages. I had sprite issues until I bumped up the +5 voltage.
      From what I read sprites are NOT affected, only background.
      Yes, and checked my voltages first up. All game sprites seem fine. Its just some of the background being effected by these vertical bars as seen in the pics.
    • Apocalypse wrote:

      jassin000 wrote:

      I'm no expert, but I would think if it was RAM you would still get sprights they would just be garbled/wrong.
      The fact the sprights are missing at repeating locations seems like failing custom.

      -Ace- wrote:

      Check the voltages. I had sprite issues until I bumped up the +5 voltage.
      From what I read sprites are NOT affected, only background.
      I had sprite issues- background was fine-
    • It seems only backgrounds are affected.The BG circuit lies entirely on bottom board.As @Apocalypse said I've reproduced a custom which is used for tiles generation but the problem could also be elsewhere.Usually these Irem boards suffer from bad Texas Instruments TTLs which fail like the Fujitsu ones.

      The post was edited 1 time, last by caius ().