Hi all,

i have an extraneous behiavor of a 16f48a, the same circuit, with the same
program, sometimes start about 5 minutes after power on, sometimes don't
start at all and another times it works fine. still is in protoboard, but
it's a simple circuit.

in software, i have this configuration (BoostC)

#pragma DATA _CONFIG, _BOREN_OFF & _CP_OFF & _DATA_CP_OFF & _WDT_OFF &
_LVP_OFF & _MCLRE_OFF & _XT_OSC & _PWRTE_ON

the circuis has a external 4MHz xtal oscillator, coupled with a pair of
22nF condenser to ground. all of this is near the pic, the pic itself is
decoupled with a 0.01uF and the only other component in the protoboard is
a 16x2 display.
about 50cm apart, is the "1st floor" of the circuit, a 3-8 decoder, 6-not
gate and a uln2003 (i think) driving 6 relays, transformer, lm7805,
electrolytic & decoupling condenser, etc, the power supply.

- the power on can be done at the transformer o "switching on" only the
protoboard (pic + display). same result
- there is nothing connected to the relay, the relays don't turn on (or
almost don't click) on power on
- when the pic start, it switch on / off several times the relays, it
works fine
- i don't have a datasheet of the xtal, it's 4MHz generic.

anyone have some idea of what happen?

thanks.

RVP



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