square signal@900Hz 2.5V; 256=1.25V, delay=100us, jitter=100us
same: square signal@900Hz 2.5V; 256=1.25V, delay=100us, jitter=100us
setup digital detection for 5V signal: very small jitter <1us. ADC might need prescale 16 (or less) to achieve 50kSps -and free run ?-.