The Casio CP-10 has a very similar or identical printer mechanism to the FP-12. I take out a mechanism from a ruined CP-10 and have a go at driving it with a Blue Pill. Some more details on the blog: https://trochilidae.blogspot.com/2021/03/using-thermal-printer-mechanism.html ... https://www.youtube.com/watch?v=3E8-rzR4IKk

The Comms Link ROM can now use Bluetooth as the 6303 serial hardware has been emulated. ... https://www.youtube.com/watch?v=_GC4zqrhKq8

This uses a casio fx-502p and and Arduino to control the flashing of a light bulb. The light bulb is an old Belisha beacon (https://en.wikipedia.org/wiki/Belisha_beacon) that I dug up in my garden, I've no idea how it got there. The bulb is a 60W mains filament type that is driven by a BTA204 triac which is in turn driven by a MOC3041 which is driven by a transistor attached to one of the digital outputs of an Arduino Due. The Due flashes the lamp at a particular rate, the rate being set by a Casio fx-502p. The Casio sends a data stream in Kasas City type format to an Arduino shield on the Due that turns the 1200/2400Hz signals into square waves, the Due code then decodes that into numbers. One of the numbers (the 'file number', the Casio's equivalent of a file name) is used to control the half-period of the flashing cycle The bottom two digits are used so 0 to 99 is approximately 2Hz to 0.5Hz. ... https://www.youtube.com/watch?v=dzFQdBvnSlo

This is a decap of a quartz watch control IC. There are die shots at the end of the video. Decapping doesn't have to be done using nasty acids... ... https://www.youtube.com/watch?v=jxPNGlKMGYM