Stlacenim zapni/vypni

[Snail Instruments]

>Pin RA4 sice nema osazeny spinac proti VCC, nicmene je tam ochrana dioda
>oprena proti VCC, takze napeti na tomto vyvodu muze byt max. VCC +0,6V.

S tou ochrannou diodou je to pravda - s vyjimkou RA4. Konkretne u 16F877:

Voltage on any pin with respect to VSS (except VDD, MCLR. and RA4) . -0.3V 
to (VDD + 0.3V)
Voltage on RA4 with respect to 
Vss.............................................0 to +8.5V

Kdybych to nekde nevidel pouzite, tak by me to taky nenapadlo.

J. Hanzal