Re: for starters

On Tue, Aug 02, 2005 at 01:21:28PM -0700, m listus wrote:
> hi again,
> thanks peter and jeff.
> i'll go for the thvp as i read some pics don't allow
> for lvp...

Most of the modern parts do. LVP is aggravating because it
takes an I/O pin in the middle of port B out of service.

Getting high voltage is pretty easy in a pinch. It can be
done with a 9V battery, a 12V zener diode, and the
moderate valued resistor already shown on the collector
of the transistor in this figure:

http://www.finitesite.com/d3jsys/proghvpv2.gif

All you need to do is tie the negative of the 9V to
the 5V line and the positive to the lead labeled 13V.
It'll give 14V. Finally tie the 12V zener between the
collector of the transistor and ground.

The transistor will ground the collector when on. When
it's off, the zener will limit the 14V from the 5V+9V
to about 12V. 

All of the trivial programmers are designed to be code
dumpers. So it's great for staging a WISP628.

BAJ