Release notes – Macro Clone Cafe

The author has previously said that he was planning “to buy a sound upgrade cartridge called FM PAQ. This is a new reproduction of the classic MSX FM PAC cartridge by Eric Boez, an MSX enthusiast in France […] I think the software and the music cartridge could both be totally amazing” so we can assume that he’s completely onboard with the idea of adding expansion hardware to computers and presumably wouldn’t be hypocritically and childishly upset should the C64 be allowed similar options. With that in mind, C64CD’s new C64 demo Macro Clone Cafe is a “mash up” of previous Code Notes entries Electric Cafe and Macrojackmix but was also written to support the SFX Sound Sampler.

Macro Clone Cafe (C64)This Commodore-branded expansion contains both an analog-to-digital converter which is used for sampling sounds and an digital-to-analog converter which is used for playing them back, both of which are 8 bit quality and it’s the latter which Macro Clone Cafe utilises for NMI interrupt driven sample playback – that might sound complicated to the author, but in real terms it’s just reading bytes of data and pushing them out through the sampler at a rapid rate. The short but sweet looping piece of music that was converted for use in this demo was created especially for it by the same person who composed the music in Macrojackmix almost three decades ago![1]

Apart from the sampled music, we’re not covering any new ground technically with this release dear reader; the bouncing veritcal sprite movement is built from half a sine curve and used to position the eight hardware sprites whilst their horizontal movement is similar to the patrolling sprites in Clone Invasion, the rolling background is merely redefining three characters in the font and there are two scrolling messages which are loosely based on the ones used in the demos we’re taking inspiration from; the upper scroller is basically using a timer that counts from $00 to $ff and, if it’s between $00 and $27, updates the line of text.

Despite a previous claim from the author that “it was impossible to access 64K RAM, no matter what programming language you used”, the uncompressed version of this demo is a shade over 60K when executing since that 8 bit sample data is one contiguous 50K chunk which partially sits “under” the C64’s ROMs and I/O space.[2]

C64 and SFX Sampler

Your correspondent’s slightly grubby workhorse C64 with neon blue power LED modification, SD2IEC memory card solution and an SFX Sound Expander

We should probably expect yet another “rebuttal” from the author because your correspondent has strayed once more from the author’s stated topic despite never having been bound by it and there might be a hypocritical complaint about the use of expansion hardware too, but until then we can pause to remember that the people producing all of the demos looked at in the Code Notes series were amateur programmers, the kind that the author falsely claims were having rings run around them by “owners of other computers, such as the Sinclair Spectrum, BBC Micro, Atari 400/800/XL, Spectravideo 318/328, MSX, etc”.

As with all other C64CD releases, the source code for Macro Clone Cafe is available in the appropriate Github repository along with a download at the C64 Scene Database (there are two files in the disk image there, the second works without the expansion present using 4 bit samples rather than 8 bit) and this demo has been delayed by a couple of days because to be officially released at a small UK scene event called Slipstock where it took first place in competition… since there were no other entries. Your correspondent still feels this is a “win” and will celebrate accordingly.

[1] Your correspondent rather enjoys how circular this ended up being!

[2] There isn’t a technical reason why it doesn’t use more memory dear reader, the length and frequency of the sample dictated it; your correspondent also wrote a couple of simpler test routines beforehand starting on Macro Clone Cafe including a “classic” 4 bit sample player (the kind with the screen disabled and coloured stripes during playback) which fills pretty much everything from $0800 to somewhere past $FF00 with the $0400 screen populated when the code finishes decompressing as well. That’s not too far shy of 63K in use, debunking the author’s fraudulent claim quite thoroughly just in case all of those programs out there doing it a couple of decades before the author even started his blog don’t “count” for some reason!

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