Yamaha Portatone PSR-6300 Demonstration Disk

Heh, that thing (or a somewhat similar model) was one of the first keyboards I played when I was young. Used it for my first micro-concert at primary school, after which I was bombarded to being the resident pianist to support the school singing, while also making piano arrangements myself. The actual school piano largely being an out-of-tune wreck that wouldn't be out of place in a haunted mansion. Ahwell, you gotta start somewhere...

Manuel: Wow, great run-down of how it works. Interesting tricks that they used. When I listed the filenames in DOS (before I imaged it) I was wondering why they had weird symbols in the filename - now I know why.

The PSR-6300 has a "Custom accompainment programmer" section and a "Music programmer"-section. So you can program 8 of your own drum patterns with bass and chord (which is quite fun) and you can also record your own arrangements (which is quite hard).

So the MSX-program never really sends any traditional MIDI-information, not any note-on / off, pitch bend etc. Instead it sends the whole Music programmer-arrangements and the custom accompainment dumps via sysex and then starts playing the arrangement (via some other sysex messages). I discovered this by looking at the MIDI data sent to the keyboard by looping it back to my MIDI interface and looking at it with ReceiveMIDI. I also think the first messages it sends are "local off".

https://undone.se/misc/yamaha-portatone-psr-6300-demonstrati...

Here is a recording of how it currently sounds. Some of the songs I recognize are:

Miami Sound Machine - Conga
Whitney Houston - Saving All My Love For You
Bananarama - Venus

I think at least 2 of them are Yamaha originals.

The reason I can tell some songs has problems is that some of them won't start by themselves without help. On the Conga-song, I tried restarting the machine after it had loaded. It will reset the different sound section volumes but it will still remember the arrangement and the custom drums - and then I was able to hear the intended bassline which was silent before. I think the tempo and volume might be off on some of the songs too.

Well, I will have to experiment more with it, maybe I could try loading / running some of the sections directly instead of the AUTOEXEC.BAS ?