Search found 54 matches

by Azerpy
Mon Jun 05, 2023 5:45 pm
Forum: Dragon General
Topic: French Dragons and the PN41503 motherboard
Replies: 8
Views: 19860

Re: French Dragons and the PN41503 motherboard

Hello all. Here is the point of view of an old french user. An interesting point is that the Secam Dragon is ready for 64 K, if you change the half good rams by 64K RAM. Nothing else to do. Besides, the circuit of the motherboard is a bit different from PAL ones, it looks like a Dragon 64. And of co...
by Azerpy
Fri Feb 17, 2023 1:51 pm
Forum: Dragon Hardware
Topic: Dragon 32 with DRAM removed, video output?
Replies: 15
Views: 17504

Re: Dragon 32 with DRAM removed, video output?

On a DragonPlus power card, the fuse of 100 mA on the -5V line may be 20 ohms. In this case, there is a fall of voltage on this line used for video.
You could try a 1A fuse for test.
by Azerpy
Wed Dec 14, 2022 2:52 pm
Forum: Dragon General
Topic: OS9 tools for the CoCoSDC
Replies: 3
Views: 5621

Re: OS9 tools for the CoCoSDC

Hello Mike Yes, you give us the very good solution. With the OS9 boot 720 k disk of Soren Roug, all is OK. I can see all the files in the two disks I enter CHX /D1/CMDS to change the working execution directory (perhaps not the best way ?) and then SDC, SDRIVE, SDIR, SCHD commands are for me, and fo...
by Azerpy
Mon Dec 12, 2022 6:45 pm
Forum: Dragon General
Topic: OS9 tools for the CoCoSDC
Replies: 3
Views: 5621

Re: OS9 tools for the CoCoSDC

Hello Mike, I found that very interesting at the moment you posted it, but as a beginner, OS9 is a very long and winding road for me. So, I have upgraded two Dragons 32 (the SECAM one, very easy, and a PAL one). The 64 K ram looks good with the MMC board and FLEX or EDITPLUS. For use of the COCOSDC ...
by Azerpy
Fri Feb 18, 2022 2:14 pm
Forum: Dragon Hardware
Topic: Dragon 32 RGB SECAM and video tests
Replies: 36
Views: 31804

Re: Dragon 32 RGB SECAM and video tests

Don't be sorry, all that's only for fun !
by Azerpy
Thu Feb 17, 2022 9:42 am
Forum: Dragon Hardware
Topic: Dragon 32 RGB SECAM and video tests
Replies: 36
Views: 31804

Re: Dragon 32 RGB SECAM and video tests

Hello Alfredo Glad to see you here again. I like your project and can help you go to the end. (I want to say again that I not the designer of the RGB schematic. I have only understood, reproduced and shared what exists on the PSU Board of my Dragon SECAM RGB). I now have got a PAL Dragon and could t...
by Azerpy
Sun Dec 12, 2021 6:43 pm
Forum: Dragon Hardware
Topic: Atom RGB port?
Replies: 3
Views: 3786

Re: Atom RGB port?

Hello Alan I have no idea about these schematics, but if the Atom has the same 6847 IC, that should work. It would be nice to see the output signals on an oscillscope. I think that the result depends on the screens you use I don't speak here about RGB outputs for VGA with TTL levels (5V) I have got ...
by Azerpy
Tue Sep 21, 2021 9:52 pm
Forum: Dragon Hardware
Topic: Dragon 32 RGB SECAM and video tests
Replies: 36
Views: 31804

Re: Dragon 32 RGB SECAM and video tests

Hello Mike Thank you for your interest and care for all those things about the Dragons. Yes you are right, I wrote on 27 july "The good input of luma is not exactly the output Y of the VDG ... For his RGB converter, Retrocant must pick up into the PAL machines and adapt with a transistor or other wa...
by Azerpy
Mon Aug 16, 2021 1:48 pm
Forum: Dragon Hardware
Topic: Dragon 32 RGB SECAM and video tests
Replies: 36
Views: 31804

Re: Dragon 32 RGB SECAM and video tests

I agree that "the more development the better" as you say John.
The RGB board seems interesting, but I understand that the MC 6847 has to be removed ...
Waiting for the schematics !