I have found a way to make short, 10 to 80 usec pulses while using the 4mhz oscillator. The SRF05 proximity detector wants at least 10 usec. If I give it super long pulses catching the following echo measurement can be a problem for PULSIN.

Sooo the following makes an 80 usec positive pulse.

SYMBOL trigright = PORTB.0
LOW trigright
HIGH trigright
HIGH trigright
HIGH trigright
LOW trigright.

One thing at a time.

Ken