Better understanding PULSIN

[Acetronics2]

Hi,

But why should the preference go for a PULSIN command first?

... just to be sure to catch the first pulse ... RCTime is somewhat "out of normal use" for the leading pulse ... result is not guaranteed !!!

Any idea why I get a result of 0 or 1 at bit 8 (sometimes bit 7)?

your scoping looks strange ... just at bit 8 !!! ... try to raise the TSOP decoupling caps value and to place a ~ 50 - 100 pF as load to the TSOP output - that could catch possible ns glitches ...

Also take care to have neat 0-5 v levels : the pic Thresold is @ ~1.5 v for TTL inputs ... and Schmitt trigger needs "good" levels ...

Have a nice evening

Alain