Of ByteBeat, weak linkage and compiler magic

I recently came across some very interesting one-line programs, which generate some primitive music from simple logic expressions – a genre which has come to be known as “bytebeat”.

Being in need of a pointless-but-fun project requiring little to no concentration, I immediately wanted to play with these programs. Implementing the logic directly in an FPGA would be perfectly possible, but I actually chose not to this time – instead I wanted to compile them for the EightThirtyTwo CPU and run the sound through the four-channel DMA sound “chip” contained in EightThirtyTwoDemos (modeled very much after the Amiga’s beloved Paula chip!).

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What You Wanted, What You Got…

Sigma Delta without Math – Part 2 – 2021-12-04

Last time around I talked about strategies for halftoning graphics, and made the key point that “noise” and “objectionable noise” are not the same thing.

I haven’t yet mentioned, though, the class of dither patterns which has been used most commonly since the advent of the desktop printer – namely Error Diffusion.

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Snake Charming with USB Audio…


A few months ago I bought a couple of the ridiculously cheap DECA boards from Arrow – they’re sadly sold out now – but $37 bought you a MAX10 FPGA with 50,000 LEs, some DDR3 RAM, i2s audio, an HDMI port, USB and network ports, and a couple of GPIO headers. (It also bought you all the blue LEDs – I highly recommend not looking directly at the board when you power it up for the first time!)

I’m not the only one who’s been interested by this board – a bunch of MiST and MiSTer cores have already been ported to a DECA-based reference platform which involves a MiSTer-style SDRAM module, PS/2 keyboard, DB9 joystick and VGA video on the GPIO headers.

There is now an open-source DDR3 memory controller which has DECA as a main supported target.

And there is a project which caught my attention recently, which turns the DECA board into an external USB2 soundcard.

Yes, you read that correctly.

Naturally I wanted to try this out, so I cloned the repo on my own machine. Hmmm… there seems to be lots of Python involved. I’m not familiar with Python, but by now it’s a well-established, mature language with reliable, well-thought-out packaging and dependency management, right?

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ProjectXG Revisitied

[This is a post I made to AmiBay back in 2011.  The domain on which I hosted the images and audio snippets is about to expire, so I’ve rescued the files and moved them here – so I may as well archive the post itself too, while I’m at it!]

Anyone remember CU Amiga Magazine’s ProjectXG feature many years ago? They published a parts list and instructions in the magazine for interfacing a Yamaha DB50XG WaveBlaster MIDI daughterboard, intended for use with a PC soundcard, to an Amiga.

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Obscure obsolete media du jour

Having found that clip of the Pat Metheny Group on YouTube a couple of weeks ago, I wanted to get hold of the DVD from which it was ripped. Unfortunately it seems to be really hard to track down – I can find it easily enough on VHS, and also on Laserdisc, but not on DVD. So I acquired it by… ahem… “other means”. Since I’ve never actually handled a Laserdisc, though, I couldn’t resist the urge to buy a copy from a Stateside seller on EBay.

It arrived yesterday.


It was wrapped in newspaper, and I can honestly say this is a headline I never thought I’d see:


More Follin Fandom

It doesn’t seem to matter which platform’s sound chip Tim Follin composed for, he always seemed to find some way of squeezing more out of it than anyone previously thought possible. Here are just a few examples, found on YouTube…
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Something Completely Different

This isn’t remotely tech-related, but it’s definitely Retro.  I found this on YouTube recently and have to say I love it!

Quite apart from the musicianship, look out for Pat Metheny displaying his usual facial contortions, and Lyle Mays looking for all the world like the carny from Despicable Me!

Sadly the DVD this was ripped from (More Travels) isn’t easy to get hold of now.

ProjectXG Redux

Anyone remember CU Amiga Magazine’s “ProjectXG”?  This was a DIY project they ran, based on a hack that was published on Aminet, to interface a Waveblaster MIDI daughterboard to the Amiga’s serial port, to provide a pretty good quality MIDI tone module.

The daughterboard most commonly used for this project was Yamaha’s DB50XG, though any card which attached to a “Waveblaster” header could be used.  (Googling Waveblaster now, however, will find you a Yamaha product of quite a different nature.)

The DB50XG’s successor, the DB60XG was manufactured under license by NEC as the XR385, and this seems to be the easiest such card to find these days.  It’s very similar to the DB50XG, it just has some very subtly different voicing, and can apply its DSP effects to incoming audio as well as its own sounds.

Having built a ProjectXG many years ago, then selling it a year or so back and promptly building another one, I naturally wanted to interface a Waveblaster card to one of my Minimig variants, and listen to some old MIDI files again.
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References in videogame music

My post about the Agent X II theme reminded me of something else that’s interested me for a while. The music in computer games back in the 80s and 90s clearly contained some major pop culture influences, but I wonder how often it was completely subconscious, and how often the composer set out to copy the feel (or even the notes!) of an existing piece of music? We had a much more relaxed attitude to copyright back then!

Anyhow, the influences ranged from the utterly blatant:


Or the stunning (for 1990) game over music from Shadow of the Beast II on the Amiga, and a piece of incidental music from Miami Vice:

But sometimes it was a little more subtle.
Take for example, Rob Hubbard’s C64 music for One Man and His Droid: Listen to the section 3:05 into this:

and compare with the passage 2 minutes 40 seconds into this:

Of course, sometimes it works in the opposite direction!

So how many more examples are there?

An old favourite

After such a dry, technical post, here’s something a bit lighter: more videogame music from my childhood!

This was Tim Follin’s masterpiece from the Commodore 64 version of Agent X II. I’ve always loved the eccentric rhythms in this. (Also, listen out for a reference – perhaps accidental? – to Rutter’s ‘Shepherd’s Pipe Carol’ towards the end.)