> > But (re my earlier response) why use a transistor at all?
>
> So it's OK to short MCLR to ground with a pushbutton switch that was also
> shown on the schematic.  The transistor is required unless the MAX232
> 5V-side output is open collector, which I didn't think it was.  I don't
have
> the spec sheet in front of me right now.

(as used www.voti.nl/wloader )

Shorting MCLR with a switch is possible with a resistor from the MAX to the
PIC. An extra resistor between the MAX and the Vcc is advised to guarantee a
MCLR Voltage that is high enough.

Wouter van Ooijen
--
Van Ooijen Technische Informatica: http://www.voti.nl
Jal compiler, Wisp programmer, WLoader bootloader, PICs kopen

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