Hi, Bruce

The "GOTO Start" has to be here to allow a pulsout for each value of I ....

It works very well with no FOR -NEXT loop ...

But there's another problem on the line past "result = result >> 4" :

( with >> 4 neutralised ...of course !!! )

IF ABS ( result - refvalue ) > 100 THEN Start

Whatever the value of result ... test result is YES !!!

So, I begin to think the problem is located on the IF THEN tests ...

Note this works with R/C signals ... 1 to 2 ms pulses @ 40 Hz

Alain