What is causing the interrupts? Any change to encoder A or B?
The rotary encoder I bought simply applies pulses to one pin when spinning clockwise, and another pin when spinning counter clockwise, so I just attached the interrupts to two separate gpio pins, and sent the updates to the mouse stuff directly in the interrupt handler. I simply moved the mouse N units to the right or left if going clockwise or counterclockwise.
I’m sure it’s not ideal but it worked to play breakout. I’m still a little new to the world of microcontrollers so it’s possible that I did something dumb.
That said, they work very well.
I just checked and the LSI7366R (the version I use) is now available through Digi-Key. They have really expanded their Marketplace program. I used to have to buy them directly from LSI: it wasn't a big deal to setup an account with them, but it's nice to know that next time I can just piggyback it onto my Digikey order. Although if the delay is a couple weeks I'd have to plan ahead. They typically get them to me in a couple of days.
That would have saved me a chip :) as my project was basically an encoder-driven 8-bit binary counter.
My original design was based on an Arduino Nano with an AtMega328. Originally it was designed to read 0-10-0V position signals. This is from really old machine tools :-)
Processing encoder inputs was a much later change. With the rate of interrupts coming in from a high-resolution encoder turning at 3,000 RPM, there was no way it would keep up and still do all the processing needed.
The product volume wasn't high enough to make it worthwhile moving to a processor that had the timer/counter resources to handle it in hardware, so the simplest solution was adding a $6 chip (and a $2 differential interface chip to handle the differential encoder output channels).