Search found 42 matches

by stroebeljc
Thu Sep 24, 2020 5:03 pm
Forum: Development
Topic: What am I missing? - Calling RND from assembly.
Replies: 11
Views: 3183

Re: What am I missing? - Calling RND from assembly.

Don’t forget that the FRAMES counter only advances by one each video frame. For a 50Hz video system (Europe), that’s every 20ms. Also FRAMES only advances if the machine is generating video. Mark Excellent point! Depending on your use case, there may be any of a thousand methods to generate a pseud...
by stroebeljc
Tue Sep 22, 2020 7:47 pm
Forum: Development
Topic: What am I missing? - Calling RND from assembly.
Replies: 11
Views: 3183

Re: What am I missing? - Calling RND from assembly.

In Basic you need to call RAND without an argument before calling RND. This uses the FRAMES counter as the random seed to generate a pseudo-random number. So, if you want to write your own assembly code, I would just use the FRAMES value, AND the result with 3, and test for 0. BEGIN: LD A,($4034) AN...
by stroebeljc
Fri Sep 04, 2020 5:34 pm
Forum: Development
Topic: Splash Scree
Replies: 10
Views: 5101

Re: Splash Scree

Cool. An easy way to look at the source is to add these 3 lines: 50 FOR X=1 TO 9999 60 PRINT A$(X) 70 NEXT X Then you type GOTO 50 to show a screenfull of source code, and CONT to display the next etc. mrtinb, I am unfamiliar with MTASM and am curious about the graphics characters at the end of eac...
by stroebeljc
Tue Sep 01, 2020 4:57 pm
Forum: Emulators
Topic: [Vb81] Test release.
Replies: 32
Views: 23486

Re: [Vb81] Test release.

It still seems faster than my ZX81.
by stroebeljc
Mon Aug 10, 2020 10:40 pm
Forum: Hardware
Topic: This weekends projects
Replies: 53
Views: 14487

Re: This weekends projects

Here is another peripheral called the Parrot that is based on the same speech chip. There are some nice design references contained in this thread.
by stroebeljc
Thu Aug 06, 2020 8:05 pm
Forum: Welcome Area
Topic: Howdy from Boston
Replies: 3
Views: 3216

Re: Howdy from Boston

Welcome!

There are several libraries available. One of me favorites is here.
by stroebeljc
Tue Aug 04, 2020 3:37 pm
Forum: WANTED
Topic: Edge connectors / protoboards wanted. (UK.)
Replies: 15
Views: 9850

Re: Edge connectors / protoboards wanted. (UK.)

I did check on that site but listing is closed atm I have found someone on eBay whos got a few might be same person its same price :) It's because PokeMon closes his items when on vacation. Most of them will open again when he's back in a few days. And now it seems to be gone forever. Do you know o...
by stroebeljc
Tue Aug 04, 2020 3:30 pm
Forum: Emulators
Topic: EightyOne emulator may have bug with WAV generating
Replies: 14
Views: 6190

Re: EightyOne emulator may have bug with WAV generating

I have also had problems with EightyOne wav files. Many on this site, including me, find the Java ZX81 Tape Converter to be one of the best tools available.
by stroebeljc
Fri Jul 31, 2020 4:01 pm
Forum: Development
Topic: Pretty fast Mandelbrot set generator...
Replies: 8
Views: 5216

Re: Pretty fast Mandelbrot set generator...

Excellent!
Thanks, Bean.
by stroebeljc
Thu Jul 30, 2020 4:50 pm
Forum: Development
Topic: Pretty fast Mandelbrot set generator...
Replies: 8
Views: 5216

Re: Pretty fast Mandelbrot set generator...

It would be nice if the zoom focused on the center of the screen. It seems like I need to move the screen down 2 clicks after every time I zoom.