Hi to all engineers.

I am planing to work on  timers  that requires 5 pressure sensors
to trigger each channel separately  on and off . it is 15 to 45 minute
timer .
if any of them starts working the time switch should be locked if user
changed the time while it is working it wouldn't effect the time.
they should be independent too user may run all 5 of them also
user may reset any channel. last year I made the same thing
but 6 channels I used 6 F84 and 2 16c71 for pressure sensors. all 6
RA4 I connected together with 1 resister and that is how I controlled
the time lock. before it starts it checks if ra4 is low then it will
skip the switch test
Today my boss asked me to make same thing again
this time I want to add 2 led display for each channel . My question is
witch method should I use should I use real time clock or watch
crystal will be easier any recommendations will appreciated.

Andre