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Main => Consoles => Topic started by: shess on May 23, 2006, 12:07:37 am

Title: dreamcast and scart on arcade monitor
Post by: shess on May 23, 2006, 12:07:37 am

I know this subject has been brought up before, but I can't seem to find the answer I need.  I'm doing the scart mod using the info from the dc2jamma pages, but I can't figure out how to enable 15khz using the scart cable.  I know I need to disconnect pin 6 on the Dreamcast, but is there a way I can do it without modifying the DC motherboard?  Yes, I'm sure the vga box should have been the way to go, but I've already started doing the scart method.  Anyone know the solution?

Thanks,
Scott

Title: Re: dreamcast and scart on arcade monitor
Post by: shess on May 23, 2006, 09:37:47 am

Well I took a risk and decided to cut the pin anyways from the DC's motherboard and thankfully it's not all fubar'd.  So I get a halfway decent pic on the screen, but I think there's something screwy with the sync because it's not a straight picture.  I tried playing with all the dials and nothing made it better.  My jpac also has some issues related to sync I believe too...  Before I just hooked up a vga cable to the monitor cable so it had separate sync, but to make the jamma connector I connected H and V sync together.  Could that be the problem?  Should I be using Pos sync or Neg sync from the monitor?  I'm using negative sync right now.  Thanks for the help!

Scott

Title: Re: dreamcast and scart on arcade monitor
Post by: shess on May 23, 2006, 12:59:57 pm

After further inspection I noticed something odd with the composite sync/video circuit.  The picture doesn't change whether I turn the circuit on or off.  Maybe my circuit is busted?  Everything appears to be connected properly, but what voltages should I expect to see on different pins or what else should I look for?  I didn't solder directly to the chip, but to a chip socket.  Sorry for the multiple posts, but this is just frustrating the crap out of me.

Scott

Title: Re: dreamcast and scart on arcade monitor
Post by: shess on May 24, 2006, 06:38:30 am

Well, I figured it out.  Turns out my scart cable from lik-sang was wired up wrong, but in a good way!  Pin 20 was supposed to carry the composite video connection which would feed into the circuit I built.  Turns out Pin 20 was carrying composite sync!  So I just connected the wire directly up to the fingerboard, played with the knobs a bit and now the picture is perfect!  Woohoo!

Scott

Title: Re: dreamcast and scart on arcade monitor
Post by: *ShAgGy* on June 11, 2006, 12:05:45 am

lol YAY!
your gave the answer i was gunna give without me having to write it!! :D
lol

 :troll:

Title: Re: dreamcast and scart on arcade monitor
Post by: Dave_K. on June 11, 2006, 08:10:48 pm

Glad you figured it out.  There are two types of scart looking cables, Euro (scart) and JPN (rgb).  Both pinouts are documented on gamesx.com.

http://gamesx.com/wiki/doku.php?id=av:scart_connector
http://gamesx.com/wiki/doku.php?id=av:japanese_rgb-21

Title: Re: dreamcast and scart on arcade monitor
Post by: shess on June 12, 2006, 03:16:06 pm

I was worried about the different pinouts but looking at the differences between japanese rgb and european scart, my cable is exactly like the european scart except for pin 20.  I think it was just a screw up from Lik-sang...but no worries, it worked out in my favor.

Scott