Implementing MIDI pitch bend signals into MIDISID

I've long thought of MIDI as being 'stepped', locked into the 127 notes in semitone intervals. 

I've been aware of pitch bend wheels on MIDI devices, but that has seemed like some dark art to me and a look at the documentation doesn't help to allay that opinion.

Before the gory details, here's a short video showing MIDISID with pitchbend successfully implemented, first with MIDI input from Logic Pro and then with keyboard input (the only keyboard I have with a pitch wheel)

The MIDI message is Ex where x is the channel. There follows (usually) two bytes, each supplying 7 bits of a 14-bit number, the 7 least significant bits first. When you have your 14-bit number, that'll be hex 2000 if the wheel is in the centre, going down to 0000 and up to hex 4000. I believe that this usually represents a tone each way (though there are other messages that can set the 'sensitivity' of the wheel).

I procrastinated with this feature because this seemed way too scary. But in fact it's really straightforward, taking just a couple of lines of C to build our magic number:



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