11438RE: [beam] My Little Buddy
- Mar 1, 2001Looks like you need resistors in series with the LEDs. Try resistor values
between 470 ohms and 4.7K. The resistors will probably be different for the
RED and Blue LEDs because of the difference in voltage drop. Since both LEDs
come on at once that indicates they are connected from the output to +V or
GND and the bicore process is dead with both inputs or outputs at +V or GND.
Don't panic! The chip is still OK but both microcores and bicores can stop
working if the process is killed off. In a microcore just hold one input at
GND for a short while and the microcore process dies. With a bicore just
apply +V or GND to one input and bingo it stops working with both inputs at
GND or +V. Depending on the LED common that causes both LEDs to be off or on
and stay that way unless a process is injected or some leakage current
causes one input to drift to the threshold voltage. You can avoid this
problem by adding a large resistor in parallel with each bicore inverter
(sort of like the reverser circuit). Those parallel resistors should be 10
times greater value than the input to input timing resistor. The details of
this were posted back in Nov/Dec 1998 under the heading ABC Bicore which I
believe was the first contribution worth noting to this list.
Sent: 2/28/01 8:38 AM
Subject: [beam] My Little Buddy
Well, I took my first Bicore and added in photoresisters and a
Seems to work...
Check it out..
One thing that is a problem I can't seem to figure out is he was working
where the two LEDS(the Motor) would flash alternatively..., and if it
taken into a completely dark room the LEDS would stop flashing....
Also, if you presses the touch sensor it would double the speed the of
But for some reason, now both LEDS stay on, no flashing...
if you take it into a Dark room the Blue LED will Plum out...
and if you hit the touch sensor while in the dark room the Blue LED Will
Turn back on...
Anybody know how I can get it to flash again
I check the Circuit for shorts, couldn't find any...
It hasn't changed physically as far as I know, but it has changed the
it works somehow...
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