Dan Michaels email (remove spam text)
Tony Nixon wrote:
>It now has user set verification voltages from 2V to 6V in 0.25V steps
>and can be easily calibrated at anytime by the user.
>The PIC's are supposed to be programmed with VccP at 5V, but can be
>verified afterwards at lower or higher voltages.
Hi again Tony,
Another potential hazard occurred to me. If the programmer does
power the target during ICSP [which you apparently will have to
do if you want to both program at 5v and then test over 2-6v],
it is likely that the programmer will be back-driving current
into the v.reg on the target bus.
I dealt with this problem on the new PIC'40 SBC that I am producing
by having a jumper for isolating the v.reg from the bus. You might
want to suggest something similar in your PP ops manual.
BTW, anyone got a good feel for how a v.reg reacts when you
power it up from the wrong direction - or otherwise drive its
ouput node higher than its input node?
[proactive response --> hmmm, just as I thought].
- Dan Michaels
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
See also: www.piclist.com/techref/microchip/devices.htm?key=pic
You must be a member of the
piclist mailing list
(not only a www.piclist.com member) to post to the