+ TCCR3A = ((0 << WGM31) | /* normal mode, OCR3A */
+ (0 << WGM30)); /* normal mode, OCR3A */
+ TCCR3B = ((1 << ICNC3) | /* input capture noise canceler on */
+ (0 << ICES3) | /* input capture on falling edge (don't care) */
+ (0 << WGM33) | /* normal mode, OCR3A */
+ (0 << WGM32) | /* normal mode, OCR3A */
+ (3 << CS30)); /* clk/64 from prescaler */
+
+
+
+ TIMSK3 = (1 << ICIE3); /* Interrupt on input compare */
+