Are there any projects out there designed to write data to with

I don't know about cassette tape, but there is for minidv. You need to have firewire and a minidv camcorder.

>>57105515
There are, but if you write one yourself I'd totally check out your source code. I have a high quality cassette player from the eighties and all these 100kb files I'd like to backup.
You could look at how dialup encodes digital data, or design your own method with wavelets or combined tones.

>>57106664
You can easily back it up to .wav files as-is, anon.

>>57105515
None I know.

But you could use OpenAL to write to audio, plug in cassette recorder, for saving.
Play back, record with openAL, reconvert for reading

Controlling a cassette deck automatically is also an option. If I had to do that right now somehow, i'd try to use a raspberry pi, wire the gpio to relais to control the tape deck, plug the audio interfaces to the aux of the tape deck and control a program like mentioned above it via http interface.

>>57106664
I did some digging and yeah, there ARE apps designed to do this already, but they're all specifically built for backing up older tape formats. Which is fine...

But I may have to build it myself, to get it working as a general purpose read-write setup that isn't needing to meet the limits of 40-year-old computers.

>>57105515
you can make a program that analyzes the midi data, save midi triggers as a wav or mp3 file, then re-record them onto the cassette.

Then use audio out > mic port/sound card > have midi analysis open and it would base off of whats on the cassette tape.