exxos's Atari, Amiga & retro forum

Pin 19 seems that it has to be grounded on the falcon side to get it to work.

http://gossuin.be/images/schemasatari/A ... DAPTER.pdf

DoG wrote: 23 May 2021 21:01 Pin 19 seems that it has to be grounded on the falcon side to get it to work.

http://gossuin.be/images/schemasatari/A ... DAPTER.pdf

Oh yes of course! I forgot, it's also in the instructions I've got. I'll make a toggle switch for RGB/VGA which puts the corresponding pin to GND. Thanks @DoG :)

Hey @DoG I wired up the VGA/RGB switch but still no output. I am just asking the owner what the history of the monitor port is and why it was removed. I have a feeling that its output wasn't functioning initially since I'm quite sure I've wired this up correctly.

I noticed that the video DAC has been replaced before, the soldering looks DIY and there are traces of flux I can see.

Do you think I should put my oscilloscope on to measure R G B H V? Or any other particular area.

@exxos I remember recently you replaced a falcons DAC for a customer, how did you come to the conclusion that it was at fault & what can I check to confirm? (if explaining oscilloscope stuff pls do with some detail as you know I am still learning the scope)

https://www.exxosforum.co.uk/forum/viewt ... p=206#p206

IIRC that was not outputting signals on all RGB channels.. but it turned out it was not receiving them from the Videl .

exxos wrote: 24 May 2021 14:56 https://www.exxosforum.co.uk/forum/viewt ... p=206#p206

IIRC that was not outputting signals on all RGB channels.. but it turned out it was not receiving them from the Videl .

Okay, so this is a little different since I'm not getting any sync at all. So in my case I guess I'd need to trace the h/v sync signals back? What do you think. Is sync generated by the DAC?

ps - I know the falcon is 'working under the hood' because of the normal floppy access during detection/startup and after memory test.

Steve wrote: 24 May 2021 17:07...
Okay, so this is a little different since I'm not getting any sync at all. So in my case I guess I'd need to trace the h/v sync signals back? What do you think. Is sync generated by the DAC?
...

DAC is only for the RGB bits to analog. VIDEL is making CSYNC, HSYNC and VSYNC.

Thank you my friends, this points me in the right direction, my investigation continues :)

Okay,

I decided to go back to making a DB19 connector, based on @DoG 's idea of cutting down a DB25. I just want to make sure this Falcon looks proper and original, do I decided against a custom VGA solution.


Seams soldered together and sanded. Looks good :)