Search found 65 matches

by Bean
Thu Aug 22, 2019 1:45 am
Forum: Hardware
Topic: What else might be connected on the ZX81 alongside the ZXPand+ ?
Replies: 17
Views: 3632

Re: What else might be connected on the ZX81 alongside the ZXPand+ ?

I am having a problem using the ZXPand "Version 2.5 Dragon" with my ZXGame interface. My interface uses the 8K to 16K area, but the ZXPand interferes with it even after I do CONFIG "M=H" and a CONFIG "M" show it as 16K - 48K. But if I poke the 8K to 16K region it will return what I poked. So it is a...
by Bean
Tue Aug 13, 2019 1:44 am
Forum: Development
Topic: New hardware I/O board using Parallax Propeller (VGA,Sound,Joystick,etc)
Replies: 32
Views: 11584

Re: New hardware I/O board using Parallax Propeller (VGA,Sound,Joystick,etc)

Using the existing 4 color mode and just setting the palette to the 4 gray scales in the 64-colors available would create a 2-bit grayscale screen. The price could be less than $100, but I'm not sure just yet. Might be as low as $50 for the kit. I will have to see. Again, the big advantage of the bo...
by Bean
Fri Aug 09, 2019 10:13 pm
Forum: Development
Topic: New hardware I/O board using Parallax Propeller (VGA,Sound,Joystick,etc)
Replies: 32
Views: 11584

Re: New hardware I/O board using Parallax Propeller (VGA,Sound,Joystick,etc)

Personally I think it's not interesting, as it will only work with software custom made for the device. True, that is a fair point. The advantage is that you can run the ZX81 in FAST mode, which really unleashes the speed. Machine code is crazy fast.. I don't plan to sell a bunch of these. It is mo...
by Bean
Fri Aug 09, 2019 2:23 pm
Forum: Development
Topic: New hardware I/O board using Parallax Propeller (VGA,Sound,Joystick,etc)
Replies: 32
Views: 11584

Re: New hardware I/O board using Parallax Propeller (VGA,Sound,Joystick,etc)

I haven't heard from anyone... I have pretty much decided on: VGA 640x200 2 color VGA 256x192 4 color (2 pages for page flippin' games) VGA 160x100 64 color Stereo sound (3 voices+1PWM left, 3 voices+1PWM right) Wii Classic Controller for joystick I plan to offer it as a kit for about $100 - $150. A...
by Bean
Wed Aug 07, 2019 2:00 pm
Forum: Development
Topic: New hardware I/O board using Parallax Propeller (VGA,Sound,Joystick,etc)
Replies: 32
Views: 11584

Re: New hardware I/O board using Parallax Propeller (VGA,Sound,Joystick,etc)

I am working on the VGA modes and I was wondering what everyone thought would be good modes to have for games and such. I have about 16K for video memory and maybe another 2-4K for palette info. So with that in mind here is what I came up with. Text: 80x25 (not sure about what is possible for colors...
by Bean
Tue Jul 30, 2019 2:06 am
Forum: Development
Topic: New hardware I/O board using Parallax Propeller (VGA,Sound,Joystick,etc)
Replies: 32
Views: 11584

Re: New hardware I/O board using Parallax Propeller

Martin, Yeah, that is the bad part. This is only an I/O board with an on-board processor. So there is no code "built-in" that the ZX81 can run. I wish the ZXPand had a pass-thru connector. I have put a 16K RAM on it just because my board doesn't have a pass-thru either. Just the be clear, the VGA an...
by Bean
Sun Jul 28, 2019 8:11 pm
Forum: Development
Topic: New hardware I/O board using Parallax Propeller (VGA,Sound,Joystick,etc)
Replies: 32
Views: 11584

Re: New hardware I/O board using Parallax Propeller

A couple questions... Is there something small I can type-in to see if my 16K memory supports true hi-res ? Second, should I support atari joysticks/paddles or Wii NunChuk/Classic controller ? Third, I plan to support VGA, but what about composite video ? Right now it is going to have: VGA Text 80x6...
by Bean
Thu Jul 18, 2019 2:42 am
Forum: Sinclair Misc
Topic: Why did Sinclair resist Floppy drives for it's computers ?
Replies: 4
Views: 2824

Why did Sinclair resist Floppy drives for it's computers ?

I am just wondering why Sinclair was so resistant to making floppy drives for the ZX81 and Spectrum computers ? I believe this is what kept them firmly in the "toy" or "game" computer category. Certainly not seen as a "real" computer by much of the public. I know they would have been expensive, but ...
by Bean
Sun Jun 16, 2019 4:59 pm
Forum: Development
Topic: New hardware I/O board using Parallax Propeller (VGA,Sound,Joystick,etc)
Replies: 32
Views: 11584

Re: New hardware I/O board using Parallax Propeller

Does this look correct for 16K that is True Hi-Res compatible ?

P.S. I forgot to show that /RAMCS is tied high too.

Thanks,
Bean
by Bean
Thu Jun 13, 2019 4:02 pm
Forum: Sinclair Misc
Topic: Did the original ZX80 "new" ROM really contain.....
Replies: 3
Views: 2973

Re: Did the original ZX80 "new" ROM really contain.....

Somewhere I saw a picture of the prototype keyboard and it did have those keywords. The story I heard was when the printer was developed those commands had to be removed since the ZX81 pretty much has to do all of the printer control. This is a shame, as those commands would have been really nice to...