Re: [cosmacelf] Re: VP550 on LP
- I couldn't find any info on PIN-8 (Play It Now), either.
Perhaps it's lost to the ether.
It's not a "full spectrum" of notes on the musical scale, and durations, and other musical possibilities,
which is why the music played is a little (or a lot) simplistic: (?)
"Music is encoded from sheet music with note pitch and duration being described with a single 8-bit byte.
PIN-8 is structured so that unique measures need only to be encoded once and can be used in any sequence.
The amplitude envelope of a note can be controlled to have one of 16 values for each of 16 time segments of a note’s duration."
There are only 12 notes on the chromatic scale. So you could get 4 more aditional notes above or below an octave,
perhaps Middle C. Or you might use one as a non-sound rest. Any minimally complex music spans octaves, usually,
so there might have also been some Up/Down shift commands, which one of the four could also be used for.
Off hand, I would maybe set them to be: 0 = rest; 1 = Shift Octave Up; 2 = Shift Octave Down; 3 = Set Octave to Middle C
And then you could do something similar with the 4-bit duration nybble, too. Depending on how many durations you want
to support. Minimally, it would probably be 1/16, 1/8, 1/4, 1/2, and Whole. So, unless you want to play some "fancy"
music (1/32 and some other things like that -- it gets REALLY 'complex'), you have some extra coding available there, too.
Here's some 1802 (? -ish?) software I didn't know about: (CHIP-8-based, which I believe works on other CPU's, too)
MegaChip8 devkit (2007)
I will encourage anyone willing to attempt CHIP-8/SUPERCHIP/MEGACHIP8 development.
This devkit will provide you with everything you need to start developing games:
This Devkit contains everything you need to start Chip-8/SuperChip/MegaChip8 development
- The Super/Mega/Chip-48 Assembler V2.5 by Christian Egeberg (MegaChip8 extensions by: M. Wenting / Revival Studios)
- MegaChip8 specifications/documentation, full opcode list for CHIP-8/SuperChip/MegaChip8.
- CHIP8_BMP.EXE - Convert BMP images to CHIP8-Assembler include data.
- CHIP8_WAV.EXE - Convert WAV files to CHIP8-Assembler include data.
- Small MegaChip8 example sourcecode.
The devkit is available from the download section of the website.
And there is some more interesting stuff there, too.
On 3/14/2013 5:12 PM, urrossum@... wrote:
> A few tunes recorded from a Cosmac computer. Sounds pretty good too.
I'm not sure about sounding all that good - the intonation isn't particularly good, but the amplitude envelope is a lot less "bleepy" than I'd expected.
I'd like to find out more about that PIN-8 music language - that's some pretty serious compression, encoding both pitch and duration into a single byte. Does anyone have any more documentation about it (my Google Mojo wasn't good this time)?