Putting the BBC Micro compressed VGM to the side for now as I can't get it to work at the required speed. Instead, I've been looking at some of the Tim Follin archives posted by @breakintoprogram.co.uk to GitHub to see if I can get any of the classic beeper music playing back on the SN76489: 🔊

While I continue to battle with compressed VGM playback streaming from disk at a decent speed, here's some brand new BBC Micro music by Enfys from Outline 2026. 🔊

Some progress! I now have compressed VGM files (.VGZ) streaming from disk and decompressing on the fly. How do I know it's working? At the very end of the clip you can make out the GD3 strings. Very close to having a streaming, decompressing, SN76489 VGM playback engine. 14KB expanding to 95KB.

Buffer size reduced to 2kb which leaves plenty of memory for vgz decompression. 8271 floppy disk controller support fixed. 60Hz VGM playback fine. So now I'll work on a basic streaming decompressor to a ring buffer for VGZ. The window should be 32kb (which I don't have free) but we won't need that.

This took a lot more effort than I thought it would, but after three rewrites I finally have the VGM files streaming directly from disk, being parsed and played back with no noticeable stalling. This is a 125kb VGM that wouldn't fit in the BBC Micro's standard 32kb. Next... on the fly .vgz inflate.

This might not look like much, but it's 149KB of uncompressed VGM data streaming from disk on a BBC Micro with a total of 32KB of memory. Next I'll add the inflate decompression to the streaming and hopefully playback to the SN76489. 🤞

Something I've wanted to do for a while is create a generic .VGM / .VGZ player for the BBC Micro. Here's stage 1... deflate the .vgz file in memory, read the VGM header and GD3, setup interrupt based on playback speed and send to the SN76489. Next step is to look into streaming playback and SWRAM.

This is awesome @ramtopretro.bsky.social ! youtu.be/JeNx-OwGDXg

My universal converter for the BBC Micro SN76489 now contains support for over 15 PSGs and 20+ different input file formats. Most of the converters have been rewritten from scratch. Here's the latest addition... the .sndh converter that shares code with the .ym and .ay converters now. 🔊

I've been working on a universal music converter, and revisiting some older tools to include. Here's a much improved SAA1099 to SN76489 converter that I'm integrating (Any glitches are my rudimentary player). All my converters use an intermediate format before I compress to 3 tone/1 noise channel.

As converting NES .nsf files is very similar to converting .hes files, it didn't take much to add this to the converter. As a bonus I added VRC6 support too so I could convert some of the tracks from Castlevania 3 - Dracula's Curse JP. Need to find a good source of new modern .nsf files now. 🔊

Continuing my PC Engine HuC6280 to BBC Micro SN76489 converter. I've added support for .HES / .m3u files as input which expands the available content for conversion. It also tries to intelligently compress the channels down to three tone and one noise. Not too bad so far. 🔊

I've been working on a new HuC6280 (PC Engine/TurboGrafx-16) to BBC Micro SN76489 converter. Quite a challenge to fit 6 channels into 3, but trying a new technique with arpeggiation. 🔊

Trying out some visualisation effects in the player, making better use of the space and moving the track metadata into the scroll text. Broken a few things along the way, but so far working okay even with the software bass active. Now to reduce the number of cycles it takes to display. 🔊

Acorn Electron版 AWASS #acornelectron inufuto.web.fc2.com/8bit/awass/#...

I thought I'd give the Acorn Electron port of the Squeeker Plus 1-bit engine a go, not expecting much considering the demands on the faster BBC Micro. However, venturing into the murky realms of illegal NMOS 6502 op codes, it's playing!.... badly, but it's at least recognisable with its issues.

Very much a work in progress, but quite a while ago @h0ffman.bsky.social shared his .1tm file for 1-Bit High and Rising. The intention was to port the Z80 Squeeker Plus engine to the 6502, but it proved to be difficult... until now. Pitch is wrong.... but it's finally playing . More work to do! 😊

Today's demo effect on the BBC Micro... the iconic spinning cube. Here's a very basic version with backface culling. I wasted 10kb on double buffering, so there's only room for a short sound loop on this one. There are much better spinning cube examples already on the Beeb. 🔊

Today we have a classic scroller on the BBC Micro with a slight twist... custom font scaled dynamically to 16x16 pixels and continuous gradient applied to give the impression of more colours than supported by Mode 5. All software scrolling (no CRTC abuse) so works on the Acorn Electron too. 🔊

Another attempt at a BBC Micro Mode 7 demo effect today - the Moiré pattern. Could do with some colour and further optimization, but just wanted to get the basic effect working. This demo is accompanied by some classic Mad Max {Jochen Hippel) music. 🔊 #bbcmicro #demoscene

More 6845 CRTC experimentation on the BBC Micro. This time it's Mode 1 and an infinite vertical scroller. I'm probably not doing this right as it's not as smooth as I would expect. Need to do some more reading on this one. No music with this demo. #bbcmicro #demoscene

Experimenting with the BBC Micro's 6845 CRTC to do some smooth full screen hardware scrolling. Not something I've attempted before and I can see a number of possibilities. This is a simple Mode 5 dynamically generated gradient that I'd have a lot of difficulty moving at this speed in software. 🔊

Today's demo effect on the BBC Micro... water ripples. This would be much better in higher resolution so I may try a Mode 1 or 5 version. It doesn't quite follow the original algorithm due to the resolution constraints. 🔊 #bbcmicro #demoscene

Another demo effect on the BBC Micro with music... it was going to be a dot tunnel demo but I haven't yet got the tunnel effect working, so here's a variant. 🔊 #bbcmicro #demoscene

Today's BBC Micro demo effect.... it was going to be a rotozoom, but I can't get the rotation looking right or at a reasonable speed at the moment, so here's a panning, zooming checkerboard with music. 🔊

Experimenting with trying to recreate some classic demo effects on the BBC Micro, starting with plasma. The version I have in Mode 5 looks better, but was slide show speed so moved to Mode 7. Needs more optimization, and the plasma effect can be improved. Added some music too. 🔊

Ok, this is about as complete as it will get 😊 Here's a preview... I'll tidy up a few things (maybe change the music) and post on Stardot. 🔊

Stage 2... need to optimize the snow fall some more, and then add the interrupt-driven music. 🎅

Not sure where I'm going with this yet, but I'm determined to make a little festive demo for the Acorn Electron. I have some music ready. Watch this space. :-)

I've released a beta of the first BBC Micro David Whittaker Music Disk here: www.stardot.org.uk/forums/viewt... Looking to get some feedback on compatibility with real hardware before I publish the final version to my website. Still may be one or two small bugs to fix.

I now have the ability to use 16kb of main memory if no SWRAM is present on the device, so those without at least get to hear songs that fit into that space and partial songs from those that don't. This also works for songs where you don't have enough SWRAM banks to fit the whole track.

Getting closer to releasing a whole batch of music disks I've put together for the BBC Micro. Spending some time on cycle-optimising the music driver as even two or three cycles make a difference when called in the main play loop. At the moment it requires SWRAM - about to fix that...

Here's a hint where I'm going with this sample sequencer. I've moved the playback loop to zero page and leave the WE (write enable) active which allows output of 16kHz samples (although memory becomes an issue). Need to combine this with my SN76489 conversion of the SID.

Just a little something I'm working on. This is RLE encoded for fast playback, but I'm sure I can compress the samples better to fit more in memory / SWRAM.

Some further progress! The ROM version of Speech! is now working on the Acorn Electron. The speed difference, and hence the quality of the sound, is quite dramatic. Hopefully that's the whole disk and demo programs converted now. I'll package this up properly and post a link on Stardot.

Acorn Electron Speech! Here’s a work in progress build for you all to try on @0xc0de.bsky.social ’s excellent emulator. Not sure the SWRAM version works yet, so load option 1, then CHAIN “DEMO” or reboot the disk. 0xc0de6502.github.io/electroniq/?...

Getting better... here's the official Speech! demo converted to Mode 6 on the Acorn Electron. This is still just using main memory. No speed up from SWRAM yet.

Well... it sort of works 😊 A lot of optimization needed, but I have a full disassembly that compiles to a byte identical binary and is relocatable. Speech! on the BBC Micro uses 4-bit values for attenuation, which I have to reduce to 1-bit on the Acorn Electron so quite a bit of fidelity is lost.

A release soon 😊. Still finding uninitialized memory bugs causing random crashes... but getting there...

So, three double sided disks of tracked music conversions to the BBC Micro's SN76489 are ready. Just testing that I've fixed the random crash in the player when switching tracks, and then I'll put them up on my website. Works on both Model B and Master, but requires several banks of SWRAM.

I've always wanted to put together a simple demo effect with some background music. I've never got around to this until now. Probably the most basic Sinus Scroller you'll see, with character based positioning. Hopefully I'll improve this over time and use bitmaps. Might even add a starfield :-)

Back in 1987, Your Sinclair published a type-in listing by Tim Follin titled Star Tip 2. It was a 1-bit beeper tune. Recently David Given ported this to 6502 assembler for the Commodore PET. Hence porting this to the BBC Micro was straightforward. It's not perfect, but I'll continue to tune it.

I'm back looking at 1-bit music engines again as I want to port a few others over from the Z80. First I thought I'd revisit the SquatM engine and see if I could optimise it. The first improvement was to get the sound playing on all three tone channels of the BBC Micro's SN76489.

An SN76489 conversion of a new @h0ffman.bsky.social track from @gordon.plus's Oric demo, No Sleep 'Til Budleigh - 2nd in Old School Demo at Nova 2025. As this was converted via the Euphoria emulator in DOSBox, it won't sound 100% accurate (easier to convert .pt3 files). demozoo.org/productions/...

Another bug squashed, and now the player is working consistently on the BBC Micro and BBC Master without screen corruption or crashing. Need to soak test it for a few hours, but close now to releasing two double sided music disks of demo scene conversions.

A few more fixes so the player navigation is stable. Hopefully I can get to a point where I can release some music disks of demoscene conversions soon. Here's another SN76489 conversion you may be familiar with...

Back to working on my BBC Micro SN76489 music player. Squashed a few bugs... introduced a few new ones 😊 Made some useful optimisations on the LZSS decoder which saves a number of cycles every frame. Here's a track that may sound vaguely familiar...

A work in progress. Can't leave the enhanced version of Elite on the Electron without music ;-) Using the original MIDI tracks by Aiden Bell as the source: www.dream-ware.co.uk/elite/music/ Difficult to compress into a single channel with no volume control! 0xc0de6502.github.io/electroniq/?...

I’ve been working on more sound chip file format tools and this one’s just about ready for its first release. It converts ZX Spectrum .AY files (AY-3-8912 only… not beeper) to separate Atari YM6 .ym files. I have another converter I’ll release soon from YM to VGM. github.com/NegativeChar...