Search found 21 matches

by pianomatt
Wed Mar 03, 2021 7:33 pm
Forum: Music
Topic: Vortex Tracker help
Replies: 32
Views: 24895

Re: Vortex Tracker help

I figured it out. The previous code seems to be based on the VT tracker example code for play once and then stop. This code makes the module play over and over until a key is pressed. ORG 49120 CALL #C000 ;calling init EI ;enable interrupts Loop HALT ;wait for next interrupt CALL #C005 ;call play XO...
by pianomatt
Sun Feb 28, 2021 9:26 pm
Forum: Music
Topic: Vortex Tracker help
Replies: 32
Views: 24895

Re: Vortex Tracker help

Yes, it's currently i the middle of the track, but I have tried it at the beginning as well.

Image
by pianomatt
Sun Feb 28, 2021 8:09 pm
Forum: Music
Topic: Vortex Tracker help
Replies: 32
Views: 24895

Re: Vortex Tracker help

Sorry to revive an old thread but I'm at a loss here. I've created a track in Vortex Tracker II, compiled it as described above, assembled the loader exactly as described. Problem is I can't get the track to loop. It finished playback and just ends. I've tried it with a few different files, includin...
by pianomatt
Sat Jun 01, 2019 8:18 pm
Forum: Games/Software
Topic: Definitive list of games incompatible with +2A/+3 and of compatible versions (if any)
Replies: 158
Views: 29118

Re: Definitive list of games incompatible with +2A/+3 and of compatible versions (if any)

Thanks for the info. However: - The SpecDrum software is not a game. This is a list for games only; - There are incompatibilities between the +3/+2A and some older peripherals due to a slightly different design of the multi-purpose edge connector - some of the signals are not placed where they were...
by pianomatt
Sat Jun 01, 2019 7:58 am
Forum: Games/Software
Topic: Definitive list of games incompatible with +2A/+3 and of compatible versions (if any)
Replies: 158
Views: 29118

Re: Definitive list of games incompatible with +2A/+3 and of compatible versions (if any)

The SpecDrum software doesn't work with the 2a. In 128 mode it crashes on load, and in 48k mode no sound comes out of the SpecDrum device.
by pianomatt
Mon May 27, 2019 10:13 pm
Forum: Programming
Topic: SpecDrum programming information
Replies: 34
Views: 6136

Re: SpecDrum programming information

I got a reply from Simon Goodwin, and I'll post more details once I get a chance to reply to him. Long story short - the 7 bit kick and 6 bit samples isn't entirely accurate, but it is an ideal way of handling the samples because if you keep the volume lower on the other two groups it means you can ...
by pianomatt
Sat May 18, 2019 4:44 pm
Forum: Programming
Topic: SpecDrum programming information
Replies: 34
Views: 6136

Re: SpecDrum programming information

It might be from a magazine at the time, maybe misremembered? Then again he might mean something completely different. Either way I'm interested to hear from him because on his website he talks about using the SpecDrum in the early 90s for some demos.
by pianomatt
Sat May 18, 2019 7:49 am
Forum: Programming
Topic: SpecDrum programming information
Replies: 34
Views: 6136

Re: SpecDrum programming information

I've emailed the author to ask how he got those numbers. If he replies I'll follow up here.
by pianomatt
Sat May 18, 2019 1:41 am
Forum: Programming
Topic: SpecDrum programming information
Replies: 34
Views: 6136

Re: SpecDrum programming information

I've done a bit of a write-up on my blog of what I did and how I did it, and there are links at the bottom to the TZX and the raw blocks it contains in case anyone wants to use them as a template to make their own.

Loading your own samples into the Cheetah SpecDrum
by pianomatt
Fri May 17, 2019 11:44 pm
Forum: Programming
Topic: SpecDrum programming information
Replies: 34
Views: 6136

Re: SpecDrum programming information

So looking at the samples in a hex editor it doesn't look like the samples are limited to a 6 bit or 7 bit range. The highest peak I could see in the clap sample was -49, but the kick peaks at -51. 7 bit unsigned is -64 to 63, so while the kick is in range the clap is not - and the snare isn't far o...
by pianomatt
Fri May 17, 2019 10:09 pm
Forum: Emulators
Topic: TZX editing software for Mac?
Replies: 1
Views: 1470

TZX editing software for Mac?

Hi Everyone I've been using ZX-Blockeditor to edit and extract data from TZX files, but since it's Windows only I can only use it when I have access to Windows. Is there anything similar for MacOS? All I really need is something that will let me add and extract blocks of data in either binary or tex...
by pianomatt
Thu May 16, 2019 6:35 pm
Forum: Programming
Topic: SpecDrum programming information
Replies: 34
Views: 6136

Re: SpecDrum programming information

I'll have to have a look, but by "6-bit" I think they mean that the samples are limited to the lower 6 bits but are stored as bytes. Otherwise the samples wouldn't be so easily interpreted when importing them into audacity.
by pianomatt
Tue May 14, 2019 9:39 am
Forum: Programming
Topic: SpecDrum programming information
Replies: 34
Views: 6136

Re: SpecDrum programming information

Great sounding samples too. The only thing I noticed was, when certain samples are used together, the resulting volume is too high and there's a bit of wraparound (causing a pop). The workaround would be to lower the volume to a third of the total range, or just avoid having those samples played to...
by pianomatt
Mon May 13, 2019 9:47 pm
Forum: Programming
Topic: SpecDrum programming information
Replies: 34
Views: 6136

Re: SpecDrum programming information

Found out something else when I tried loading up my custom kit - the order the samples are stored in memory isn't the order they're presented on screen. For some reason they're all offset by one, with the last sample actually being the first on screen. So with the standard kit the kick drum is drum ...
by pianomatt
Mon May 13, 2019 5:55 pm
Forum: Programming
Topic: SpecDrum programming information
Replies: 34
Views: 6136

Re: SpecDrum programming information

I've done it! I managed to get onto a Windows PC and I downloaded ZX-Blockeditor . I loaded up the Afro Kit tzx and it's just two blocks - one with some text and the other with the raw sample data. The first block must begin with a lower case c and then each drum needs a 7 character name. I don't th...
by pianomatt
Mon May 13, 2019 3:00 pm
Forum: Programming
Topic: SpecDrum programming information
Replies: 34
Views: 6136

Re: SpecDrum programming information

Here it is in action

From one bland set of samples to another. If I can get the TZX thing figured out I'll definitely put more effort into picking the sounds.
by pianomatt
Mon May 13, 2019 2:37 pm
Forum: Programming
Topic: SpecDrum programming information
Replies: 34
Views: 6136

Re: SpecDrum programming information

I've had a pretty productive day and I've managed to bodge something together. First, the samples are stored as 8-bit signed, as pointed out by a couple of people on here. The sample rate seems to be 20 kHz, not the 16 kHz as I first thought. There are two fixed lengths for the drums - 3072 and 2048...
by pianomatt
Mon May 13, 2019 11:26 am
Forum: Programming
Topic: SpecDrum programming information
Replies: 34
Views: 6136

Re: SpecDrum programming information

I've found another TZX online with a different kit, and loading that in also saves the samples at 0x8400. The sample boundaries also line up, so maybe they're hard coded? https://i.postimg.cc/V528JsqC/Screenshot-2019-05-13-at-11-23-52.png Are there any tools out there designed to dissect TZX files t...
by pianomatt
Mon May 13, 2019 10:58 am
Forum: Programming
Topic: SpecDrum programming information
Replies: 34
Views: 6136

Re: SpecDrum programming information

I've made some slight progress by using the debugger tool in FUSE. By pure chance I found a line of assembly loading something from 0x8400, so I dumped the memory from that location and loaded it as raw sample data into Audacity. The sample rate seems to be around 16kHz, because at that sample rate ...
by pianomatt
Sun May 12, 2019 10:44 pm
Forum: Programming
Topic: SpecDrum programming information
Replies: 34
Views: 6136

SpecDrum programming information

Hi Everyone I have a Cheetah SpecDrum for my Speccy - basically an 8-bit DAC that works with some software to turn the humble Speccy into a drum machine. I've had a thorough search online and nobody seems to have any information on how these things work or what format the samples are in, so I'm inte...