Main Restorations Software Audio/Jukebox/MP3 Everything Else Buy/Sell/Trade
Project Announcements Monitor/Video GroovyMAME Merit/JVL Touchscreen Meet Up Retail Vendors
Driving & Racing Woodworking Software Support Forums Consoles Project Arcade Reviews
Automated Projects Artwork Frontend Support Forums Pinball Forum Discussion Old Boards
Raspberry Pi & Dev Board controls.dat Linux Miscellaneous Arcade Wiki Discussion Old Archives
Lightguns Arcade1Up --- Bug Reports --- Site News

Unread posts | New Replies | Recent posts | Rules | Chatroom | Wiki | File Repository | RSS | Submit news

  

Author Topic: Display Port to VGA adapter?  (Read 229 times)

0 Members and 1 Guest are viewing this topic.

pakoman

  • Trade Count: (0)
  • Full Member
  • ***
  • Offline Offline
  • Posts: 142
  • Last login:March 25, 2020, 11:24:02 am
  • I want to build my own arcade controls!
Display Port to VGA adapter?
« on: February 26, 2020, 09:09:24 am »
Hi guys.

Quick question, would this work to connect to a 15Khz Scart TV?

(I mean Display port on the graphics card - DP adaptor to VGA - Vga to Scart cable - TV)

Thanks!

EDIT I ask because everybody seems to use HDMI to VGA converters, maybe there is a limitation with Display Port
« Last Edit: February 26, 2020, 09:20:23 am by pakoman »

Calamity

  • Moderator
  • Trade Count: (0)
  • Full Member
  • *****
  • Offline Offline
  • Posts: 6865
  • Last login:Today at 05:53:18 pm
  • Quote me with care
Re: Display Port to VGA adapter?
« Reply #1 on: February 26, 2020, 10:48:09 am »
Hi pakoman,

DP to VGA works, but the dongle I tried didn't work with interlaced modes. I asked a few people on the internet and they reported the same issue.

I know interlace does work through DP, so it's probably a limitation in the chip used by the one I tried. It's this one just in case.

Also, be ready to require minimum dotclocks above 10-25 MHz.
Important note: posts reporting GM issues without a log will be IGNORED.
Steps to create a log:
 - From command line, run: groovymame.exe -v romname >romname.txt
 - Attach resulting romname.txt file to your post, instead or pasting it.

CRT Emudriver, VMMaker & Arcade OSD downloads, documentation and discussion:  Eiusdemmodi

pakoman

  • Trade Count: (0)
  • Full Member
  • ***
  • Offline Offline
  • Posts: 142
  • Last login:March 25, 2020, 11:24:02 am
  • I want to build my own arcade controls!
Re: Display Port to VGA adapter?
« Reply #2 on: February 26, 2020, 11:41:02 am »
Thanks, that helps.

Minimum dotclocks means using super resolutions or what resolution would roughly meet the minimum dotclock?

EDIT lol the adaptor seems to be exactly the same that is laying around in the office :D
« Last Edit: February 26, 2020, 11:42:41 am by pakoman »

Calamity

  • Moderator
  • Trade Count: (0)
  • Full Member
  • *****
  • Offline Offline
  • Posts: 6865
  • Last login:Today at 05:53:18 pm
  • Quote me with care
Re: Display Port to VGA adapter?
« Reply #3 on: February 27, 2020, 05:48:18 am »
Super resolutions will work in any condition. As for the desktop, if you're lucky, 640x480i might work (12.5 MHz). If you're not lucky then try width double width (1280x480i, 25 MHz), this will work for sure.

There's one limit that applies to the DP driver's implementation, and another one that applies to the dongle chip. I may be wrong but this is what I gathered from my tests. But it's been a year since I touched it.
Important note: posts reporting GM issues without a log will be IGNORED.
Steps to create a log:
 - From command line, run: groovymame.exe -v romname >romname.txt
 - Attach resulting romname.txt file to your post, instead or pasting it.

CRT Emudriver, VMMaker & Arcade OSD downloads, documentation and discussion:  Eiusdemmodi