Steve Maroney wrote:
> I'm new to microcontrollers and new to electronic circuit design. I've
> read up on how a transistor works and I think I get the theory but
> they don't function as expected when tested.

What is your training in and what level have you achieved (high school
student, college senior majoring in basket weaving, 20 years of professional
experience installing air conditioners a McMurdo Station, something else
perhaps)?  What is your background in electronics?

Where are you located?

What level of budget do you have for this activity?

> I have a PIC that outputs to an LCD which works great.  I also need to
> share 4/8 of the LCD data lines as an input to another
> microcontroller. I need a method of keeping data not destined for the
> 2nd microcontroller away from it while addressing the LCD.

Why can't you use separate communication lines?  A single UART line for each
direction pops to mind.

> I thought
> I could put some 2n2222's in line with my 4 shared data lines.

"In line" doesn't describe anything that makes sense here.  Show your
schematic.

> When testing my transistors with 5v applied to the base,

Oops.  If the emitters were tied to ground then the transistors are now
toast.

> I get the
> same voltage from the collector and emitter. The collector and
> emitter are not tied in with anything so I would expected nothing
> from the collector or the emitter.
>
> I also applied 5v to the collector and an LED w/resistor to the
> emitter. When I apply 5v to the base the LED turns on, if remove 5v
> from the collector, the LED stays on because of the 5v applied to the
> base
>
> Should it work this way ?

I have no idea what you're doing.  Show the schematic.


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