Search found 729 matches

by djnzx48
Sat Jun 06, 2020 10:11 am
Forum: Hardware
Topic: Cheetah Specdrum
Replies: 21
Views: 3029

Re: Cheetah Specdrum

I found a couple of posts claiming that two versions of the software existed, the updated version being more compatible with later Spectrum models. I suppose it's possible that your version could be different from the one in the archive. Edit: https://archive.org/stream/crash-magazine-33/Crash_33_Oc...
by djnzx48
Sat Jun 06, 2020 8:16 am
Forum: Hardware
Topic: Cheetah Specdrum
Replies: 21
Views: 3029

Re: Cheetah Specdrum

Is this the same program as the one you were using? I can get it to load OK in an emulator without the keyboard becoming unresponsive. It resets if loaded in 128K mode, as the de-obfuscation routine relies on the printer buffer being empty (and subsequently corrupts the code if it isn't).
by djnzx48
Sun May 31, 2020 11:18 am
Forum: Programming
Topic: The Definitive Programmer’s Guide to Using the Floating Bus Trick on the ZX Spectrum
Replies: 59
Views: 13213

Re: The Definitive Programmer’s Guide to Using the Floating Bus Trick on the ZX Spectrum

A relatively simple method I use to distinguish a 128/+2 machine from a +2A/+3 is checking for the existence of port $3ffd. On the 128/+2 this port controls memory paging, so you can write to it and test known memory values in the $c000-$ffff range to see if they change. If they don't, then trying p...
by djnzx48
Sat May 16, 2020 8:19 am
Forum: Website
Topic: Looking for bandit and warmtoffee...
Replies: 29
Views: 4261

Re: Looking for bandit and warmtoffee...

Hi Bandit! I think you must have got me mixed up with someone else.
by djnzx48
Thu May 14, 2020 2:40 pm
Forum: Games/Software
Topic: What's the greatest ORIGINAL Speccy homebrew of all time?
Replies: 38
Views: 6098

Re: What's the greatest ORIGINAL Speccy homebrew of all time?

You may already be aware of it, but I would also nominate El Stompo as a great original game.
by djnzx48
Thu May 14, 2020 5:58 am
Forum: Showcase your work!
Topic: Digital AY synth
Replies: 38
Views: 6336

Re: Digital AY synth

Hmm. I'm a little busy right now, but let me see if I can come up with some better explanations later. Although I'm not completely familiar with all those tools you listed, I think the difference is that the sample-based trackers operate on samples (as the name would suggest), while this program ope...
by djnzx48
Thu May 14, 2020 3:23 am
Forum: Showcase your work!
Topic: Digital AY synth
Replies: 38
Views: 6336

Re: Digital AY synth

I've now added a scrolling (well, paging) tracker display synchronised with the music. You can try it here: synth-v0.1.0-0-g2bd8639_128.tap The problem is, the rendering speed is not great (even when the code is placed in uncontended memory) and this causes noticeable gaps in the song playback. Is ...
by djnzx48
Wed May 13, 2020 5:59 am
Forum: Showcase your work!
Topic: Digital AY synth
Replies: 38
Views: 6336

Re: Digital AY synth

Very nice project :) I'm keen on trying it out on my real Spectrum. The scripts seem to be for Unix. Any idea of how I can build it on Windows? Or an already compiled version? The build scripts are designed to work on Windows as well. I should probably add some kind of README with build instruction...
by djnzx48
Sun May 10, 2020 3:27 am
Forum: Music
Topic: Re: Classical music in Spectrum games and demos
Replies: 18
Views: 16522

Re: Classical music in Spectrum games and demos

PeterJ wrote: Sat May 09, 2020 1:02 pm This is quite an interesting read:

https://www.theregister.co.uk/2015/04/3 ... um_manual/
Not on the Spectrum, but when I was looking at old episodes of '4 Computer Buffs', I found this original performance from around 1985 using Commie 64s.
by djnzx48
Sat May 02, 2020 10:34 am
Forum: Games/Software
Topic: Rooster Run - Samurai Software
Replies: 4
Views: 757

Re: Rooster Run - Samurai Software

Seems like it's a MIA title. So yes, preserve it if you can!

You could either produce a .tzx file of the tape, or upload a .wav recording and someone can make a .tzx from that.
by djnzx48
Sat May 02, 2020 2:41 am
Forum: ZXDB Discussion
Topic: Help Needed - The Type Fantastic
Replies: 86
Views: 39963

Re: Help Needed - The Type Fantastic

In the printout, listing 3 (or what the magazine claims to be listing 2) contains line 30, which skips over 368 bytes of data starting at address 64062. I loaded up 'The White Door', exported those bytes, and re-imported them into the magazine version of 'Crisis At Christmas'. After doing this the a...
by djnzx48
Sat May 02, 2020 12:45 am
Forum: ZXDB Discussion
Topic: Help Needed - The Type Fantastic
Replies: 86
Views: 39963

Re: Help Needed - The Type Fantastic

The problem occurs in lines 9958 onwards. Those variables are supposed to set up the addresses of various machine code routines, but for some reason the memory containing the addresses is initialised to zero. As a result, attempting to call the routines will cause a crash.
by djnzx48
Fri May 01, 2020 10:52 am
Forum: Emulators
Topic: Port logging
Replies: 10
Views: 2124

Re: Port logging

I just downloaded ZXSEC and it seems nice, but I don't think it does quite what I was looking for. I wanted to examine port writes in order to fix an issue I was having with a sample playback routine (individual samples were being output in the wrong order). Now those bugs have hopefully been fixed,...
by djnzx48
Fri May 01, 2020 9:48 am
Forum: Games/Software
Topic: SC Friday Quiz (TM): Skylines
Replies: 37
Views: 3803

Re: SC Friday Quiz (TM): Skylines

4. Out Run
by djnzx48
Fri May 01, 2020 8:41 am
Forum: Emulators
Topic: Testing emulators using z80test-1.0. Quick results
Replies: 134
Views: 58648

Re: Testing emulators using z80test-1.0. Quick results

In my case, it's almost surely the CPU. I'm currently using a laptop that is about 8 years old, and due to severe thermal problems I have to clock the CPU down below 1.5GHz if I don't want the fans spinning constantly. Disassembling it in an attempt to remove dust from the case didn't fix the proble...
by djnzx48
Thu Apr 30, 2020 11:52 pm
Forum: Emulators
Topic: Testing emulators using z80test-1.0. Quick results
Replies: 134
Views: 58648

Re: Testing emulators using z80test-1.0. Quick results

I've tried SpecIde in the past, and it works well, but its accuracy comes at a price. On my machine, it uses a lot of CPU and runs too slowly to be really usable. I don't know if that aspect has been improved since then, but maybe it runs better on other people's computers anyway. Last few versions...
by djnzx48
Thu Apr 30, 2020 11:23 pm
Forum: Games/Software
Topic: SC Friday Quiz (TM): Skylines
Replies: 37
Views: 3803

Re: SC Friday Quiz (TM): Skylines

24. Hysteria
by djnzx48
Wed Apr 29, 2020 11:55 pm
Forum: Emulators
Topic: Testing emulators using z80test-1.0. Quick results
Replies: 134
Views: 58648

Re: Testing emulators using z80test-1.0. Quick results

I've tried SpecIde in the past, and it works well, but its accuracy comes at a price. On my machine, it uses a lot of CPU and runs too slowly to be really usable. I don't know if that aspect has been improved since then, but maybe it runs better on other people's computers anyway.
by djnzx48
Wed Apr 29, 2020 8:26 am
Forum: ZXDB Fixes
Topic: Little bugs in the database 3
Replies: 265
Views: 59722

Re: Little bugs in the database 3

From what this article seems to say, this should be the page for Megus. Roman Petrov is not Megus, but someone who shares the same name as him. Also, they are apparently both from Russia (rather than Ukraine). Edit: if this is the case, the credit for Chopper Duel should be changed to refer to Megus...
by djnzx48
Mon Apr 27, 2020 11:01 am
Forum: Programming
Topic: Question about Dk'tronics Minder
Replies: 1
Views: 668

Re: Question about Dk'tronics Minder

I'm not really familiar with this game, but from what I can tell, the face drawing routine starts at $dd4e and calls a subroutine at $dc91 to draw the different facial features. They are drawn in this order: forehead, ears, chin, eyes + nose, mouth, with things like sunglasses and beards added after...
by djnzx48
Mon Apr 27, 2020 8:41 am
Forum: Programming
Topic: "Undocumented" Z80 index register instructions
Replies: 9
Views: 2013

Re: "Undocumented" Z80 index register instructions

I used one of those instructions to save a byte in a 64-column print routine. Since I was only operating on temporary strings, it didn't matter that the character byte in memory was corrupted.
by djnzx48
Sun Apr 26, 2020 7:54 am
Forum: Sinclair Miscellaneous
Topic: Phone wallpapers/screensavers
Replies: 105
Views: 46085

Re: Phone wallpapers/screensavers

Good idea! What do you think of these, Juan?

Image
Image
by djnzx48
Sun Apr 26, 2020 2:04 am
Forum: ZX Spectrum Next
Topic: Games behaving differently on the Next
Replies: 263
Views: 41143

Re: Games behaving differently on the Next

Yes, I would call 75 pages of text 'extensive'. But even if it wasn't, it only takes a few seconds to add someone's name to the credits if you use their work. That includes Penny Vickers and Robin Bradbeer, who contributed to the original manual as well.
by djnzx48
Sun Apr 26, 2020 12:54 am
Forum: ZX Spectrum Next
Topic: Games behaving differently on the Next
Replies: 263
Views: 41143

Re: Games behaving differently on the Next

Originally (and if you recall the early texts) it was going to be his name up there with all of ours; then the text diverged so much from the original and it ended up being written basically from scratch (not everywhere; why change a good thing?) That doesn't really make sense. The manual clearly c...
by djnzx48
Sat Apr 25, 2020 5:27 am
Forum: ZX Spectrum Next
Topic: Games behaving differently on the Next
Replies: 263
Views: 41143

Re: Games behaving differently on the Next

Is it possible to use the Next with a widescreen TV/monitor while having it display at the correct aspect ratio? Every photo I have seen so far shows stretched pixels.