The ultimate partner for the HP Prime G2 - The Arduino Leonardo.

[matalog]

Yes, I think HID itself, at least for USB 2.0, sends packets of 64 bytes - You should always receive all of them and if you want to, you can hide that you received more than you need.

There was something about the RAWHID() I remember, I had to limit sending bytes to 63 bytes from the Arduino at a time, because if I sent 64 it actually sent 2 HID messages instead of one, leaving bytes hard to keep track of. I wasn't sure why the Arduino did that.