Search found 34 matches

by Azerpy
Tue Jul 27, 2021 4:34 pm
Forum: Dragon Hardware
Topic: Dragon 32 RGB SECAM and video tests
Replies: 24
Views: 2657

Re: Dragon 32 RGB SECAM and video tests

As I explained before, the SECAM circuitry with the tunable inductors and delay device is on the mother board. I have not yet published its detailed schematics. It would be only for fun ! Is there anybody interested by a french SECAM circuitry ? On the power board, we have the RGB conversion with th...
by Azerpy
Tue Jul 27, 2021 2:01 pm
Forum: Dragon Hardware
Topic: Dragon 32 RGB SECAM and video tests
Replies: 24
Views: 2657

Re: Dragon 32 RGB SECAM and video tests

So you have a Dragon 64. When I look at its schematics, I see a LM 7905 in the video section. The diode is a clamp diode, any one is good for that like 1N914 or 1N4148. Mine is a little blue one. https://en.wikipedia.org/wiki/Clamper_(electronics). On my Dragon, this circuity is part of the power bo...
by Azerpy
Tue Jul 27, 2021 8:42 am
Forum: Dragon Hardware
Topic: Dragon 32 RGB SECAM and video tests
Replies: 24
Views: 2657

Re: Dragon 32 RGB SECAM and video tests

Hello Alfredo Incredible ! I am not yet able to create those beautiful schematics ! I have looked at yours, so I complete a little : The good input of luma is not exactly the output Y of the VDG, it should be Y + the added lines that pads the signal for use the IC 6847 in Europe (625 lines). It must...
by Azerpy
Mon Jul 26, 2021 4:47 pm
Forum: Dragon Hardware
Topic: Dragon 32 RGB SECAM and video tests
Replies: 24
Views: 2657

Re: Dragon 32 RGB SECAM and video tests

Here are the missing values of components. Happy to help you in this project.
by Azerpy
Mon Jul 26, 2021 9:56 am
Forum: Discuss This Site
Topic: new Member Spain
Replies: 9
Views: 140

Re: new Member Spain

Hello Alfredo.
For your RGB project, you can look at the Dragon SECAM schematics that I have posted in the Dragon hardware section.
That Dragon SECAM has a RGB output.
Gérard / Azerpy
by Azerpy
Sat May 29, 2021 12:43 pm
Forum: Dragon Hardware
Topic: Dragon expansions - FF00 page ports
Replies: 8
Views: 1251

Re: Dragon expansions - FF00 page ports

With a coco MiniFlash, you can choose the address of flash bank selection register
between $FF49, FF59, FF69, FF79
by Azerpy
Fri May 14, 2021 8:02 am
Forum: Dragon Hardware
Topic: Dragon to CoCo
Replies: 10
Views: 1895

Re: Dragon to CoCo

Hello again Other ways using MMC. The MMC extension board on a real Dragon or a real coco can work directly with BAS programs using MLOAD and MSAVE commands. These files, specific of MMC, have .DGN and .CCO extensions. The RETOKC and RETOKD commands is designed to convert them. If you have a real Dr...
by Azerpy
Thu May 13, 2021 5:58 pm
Forum: Dragon Hardware
Topic: Dragon to CoCo
Replies: 10
Views: 1895

Re: Dragon to CoCo

I have explained how to transfer Basic files from coco to Dragon (or reverse) via Xroar and text files on Windows. Have a look here, it's called "cross development" https://vintageisthenewold.com/coco-cross-development-part-1/ If your coco BAS program can be loaded on Xroar emulating a coco, it can ...
by Azerpy
Wed May 12, 2021 4:18 pm
Forum: Dragon Hardware
Topic: Dragon to CoCo
Replies: 10
Views: 1895

Re: Dragon to CoCo

The file.asc must be ended by a "Enter" (RC)
by Azerpy
Tue May 11, 2021 7:27 pm
Forum: Dragon Hardware
Topic: Dragon to CoCo
Replies: 10
Views: 1895

Re: Dragon to CoCo

Not sure I understand exactly what you want to do. When I want to use basic files from coco to Dragon or Dragon to coco, I use Xroar emulation and its (fine !) possibility of loading text files with the asc extension. With Xroar, I load the basic program on a virtual machine and export it with ... (...