Search found 538 matches
- Wed May 03, 2023 10:00 am
- Forum: Software Requests
- Topic: Happy Birthday Dragon Individual Games
- Replies: 6
- Views: 15585
Re: Happy Birthday Dragon Individual Games
The start, end and exec addresses for a simple binary file can be found with a few PEEKs after loading: CLOADM ST=PEEK(&H1E7)*256+PEEK(&H1E8) EN=PEEK(&H7E)*256+PEEK(&H7F)-1 EX=PEEK(&H1E5)*256+PEEK(&H1E6) CSAVEM"NAME",ST,EN,EX This won't work with custom formats such as autorun programs, but should b...
- Tue Apr 25, 2023 7:57 pm
- Forum: Dragon General
- Topic: French Dragons and the PN41503 motherboard
- Replies: 8
- Views: 21870
Re: French Dragons and the PN41503 motherboard
Hi Tony! I don't know if you've already found it but there was a discussion here on the SECAM boards a while back: https://archive.worldofdragon.org/phpBB3/viewtopic.php?f=9&t=10921 It looks like the boards need to be paired as the power connector seems to have a different layout. (i.e. resist the t...
- Mon Apr 17, 2023 4:17 pm
- Forum: Dragon Hardware
- Topic: Dragon keyboard conversion to USB HID (XRoar)
- Replies: 23
- Views: 59703
Re: Dragon keyboard conversion to USB HID
I don't really know how your setup works, but producing @ on a PC keyboard usually involving pressing shift, which may interfere with the logic at the Dragon end. Also is it coincidence that @ vs " is one of the differences between US & UK keyboards? What happens if you type into a text editor inste...
- Sun Mar 19, 2023 4:34 pm
- Forum: Dragon General
- Topic: XRoar video debug builds
- Replies: 25
- Views: 32659
Re: XRoar video debug builds
Brilliant stuff! It recreates the purple shimmer on the PMODE4 display beautifully :) To complete the Dragon video experience we would need a small and very slow drift on the colour frequency to simulate the machine warming up! @Alistair Chroma highpass can be set to zero or 0.25 to simulate the eff...
- Thu Feb 16, 2023 9:48 pm
- Forum: Dragon Hardware
- Topic: Dragon 32 with DRAM removed, video output?
- Replies: 15
- Views: 24067
Re: Dragon 32 with DRAM removed, video output?
I would have expected some kind of video display i.e. something with a border. The vdg will generate sync signals with just a clock input, except when something is pulling the CHB output down to ground activating a test mode. I've seen this happen once due to a bad ceramic cap. The video circuit req...
- Mon Apr 11, 2022 4:25 pm
- Forum: Dragon General
- Topic: OLL '22 Video Games Convention
- Replies: 3
- Views: 6662
- Mon Apr 11, 2022 2:45 pm
- Forum: Dragon General
- Topic: OLL '22 Video Games Convention
- Replies: 3
- Views: 6662
OLL '22 Video Games Convention
We had a family afternoon out at the recent OLL '22 Video Games Convention as it was close to where we live. The Centre for Computing History had quite a large presence and I was pleasantly surprised to see a D32 set up with Chuckie Egg. Of course I felt obliged to put my name on the high score tabl...
- Fri Jan 14, 2022 2:25 pm
- Forum: Dragon Hardware
- Topic: D64 with new Dragon PSU issue
- Replies: 12
- Views: 12454
Re: D64 with new Dragon PSU issue
Curious that it works in a D32. Can't really say much else without seeing a schematic and more detailed measurements.
Assuming you've followed the build instructions to the letter, the ball is very firmly in the court of the supplier and/or designer.
Assuming you've followed the build instructions to the letter, the ball is very firmly in the court of the supplier and/or designer.
- Fri Jan 14, 2022 9:34 am
- Forum: Dragon Hardware
- Topic: D64 with new Dragon PSU issue
- Replies: 12
- Views: 12454
Re: D64 with new Dragon PSU issue
I would use an oscilloscope to see how much ripple there is on the supplies. The fact that it works when more current is drawn suggests one of the supplies is moving to a more stable region, which in turn suggests an incorrect component value. A component value could be incorrect because it was put ...
- Mon Jan 03, 2022 9:45 pm
- Forum: Dragon Hardware
- Topic: Display bars
- Replies: 2
- Views: 3162
Re: Display bars
Hmm, strange one. In my experience, jail bars on Dragons are usually caused by missing bypass caps on the DRAM array, and fitting all eight 100n caps virtually eliminates them. I don't think I've ever seen hum bars on a Dragon. That tends to indicate a fault, particularly if you say 1u caps didn't m...