At 10:38 PM 3/20/00 +0100, you wrote:
>> Unfortunately, the average time it takes *me* to double the number
>> of components in my h.w. designs (ie, T2x) is only about 5 minutes.
>
>'Unfortunately' refers to your boss who carries the recurrent cost of your
>design?
>

Yeah, well ....
===========

>> Yeah, for PIC programming, one Vpp level is ok. But for *general*
>> purposes, by extending this scheme using the 2 PWM outputs of a PIC28,
>> plus sensing the voltage using the PIC's A/D channel in a stabilization
>
>OK, but now you are talking about a device that is much more ambituous than
>WISP was ever meant to be. Two suggestions from me:
>- be sure to support in-circuit programming
>- include something like the passthrough, it is so damn convenient during
>development
>

Those features are a part of what makes your WISP design so great, as
far as I am concerned. My last pass-through design [ie, last week's]
used a separate '4052 chip, but I like yours better. [unfortunately, I
have to use a bigger cpu pinout to do it - another "recurrent cost" for
my boss!].

BTW, I fiddled around some more with the PWM -> charge-pumped-Vpp idea,
and it looks like with a single PIC, you could get both +V and -V
outputs, separately adjustable, of essentially any voltage. Possibly
reinvents the switcher, but adds only about 0.25-0.50 USD to the cost
of an embedded system, and the Vpp levels are s.w./Rs-232 controllable.
===============

>> Wouter, think you could have your new '87x loader done by this weekend,
>> so Jim (Newton) could use it next week? [just kidding - keep up the
>> good work].
>
>I guess not, there is more to fill my spare time! Maybe in a week or two.
>
>regards,
>Wouter
>

Be sure to notify the piclist, once it is ready. There is certainly
a lot of interest in this area nowadays, especially from Jim Newton
and the Techref/CUMP group.

best regards,
- Dan Michaels
Oricom Technologies
htpp://www.sni.net/~oricom
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