Situation: You want to include a timer interrupt service routine in an assembly language program for an AVR-based Arduino. The program will be written, assembled and uploaded using the Arduino IDE.

license: Public Domain - please use this code however you'd like. It's provided as a learning tool. unsigned char OCR1AL_reg = 0x88; //output compare low 8 bits for Counter 1 unsigned char OCR1AH_reg ...