On Sun, 18 Aug 2002, jumanji wrote:

> Well... stuff like, don't having to worry that *that* circuitry works,
> the possibility to program it, make +5V and to decrease the soldering
> as much as possible(when ported to a project), I guess you are very
> well trained in soldering & your 300$ high-end soldering station makes
> it prolly even lots easier.

My ancient Weller WTCPN/TC201 finally died a few years ago and I haven't
replaced it, so I use a $15 25W pencil iron.  But, yes, I'm pretty good at
it having been soldering for probably 30 years or so.

I know I'm bringing up a nearly religious issue here and all, but I have
to suggest that a solderless "universal breadboard" and a box of nice
pre-cut pre-stripped pre-tinned jumper wires -- all of about $15 at your
local Radio Shack in the US, and probably similar in other parts fo the
world -- will work just fine for 99.9% of beginner projects, and the
majority of non-beginner projects.  Whoever said these wouldn't work well
with a 20MHz PIC or (insert most any peripheral function here) is simply
incorrect, I can tell you for a fact.  Stray capacitance, yes, but it's
simply not a factor for the vast majority of things you'd do with a PIC,
especially as a hobbyist, plus your oscillator will pretty much NEVER fail
to start without caps (I never, ever use them on the breadboard, have
never needed any).  I can tell you for sure that serial comms, LCD, I2C
memory, keypads, RF data transceivers, blinky LEDs, analog inputs with +
or - a few millivolts, PWM, ICSP, R/C servos, sonar, all work at clock
speeds up to 20MHz.  I know because I can look on or under my bench and
see each and every one of these, all built at one time or another on a
much-demonized solderless breadboard.  Not just a lucky one time, but time
after time, every time, without fail.  I used to keep them set up with a
7805 and a couple of .1uF caps plugged in on one end for the 5V supply,
then switched to either 3x AA batteries or a regulated supply - but I
don't think there is a PIC that won't run on 4.5V.

The entire circuitry one needs to worry about, then, is plugging a crystal
into the breadboard -- IF you're using something other than a PIC with an
internal oscillator or need to run, for example, a 16F628 at more than
4MHz.  So the only piece missing, really, is a working, solid, no-hassle
programmer.  I have mine set up with a cable that plugs into a more or
less permenently wired ISP header on the breadboard, so I can use that or
move the PIC to the programmer when needed.  I've got one 16F877 that's
probably made that trip several hunderd times, all pins are still attached
and intact.

Don't underestimate the average PIC beginner.  They may not be soldering
aces able to whip up a cheapie programmer from plans of dubious quality
found on some ages-old web page, but given a few very simple, very cheap
tools they'll be fine.

Dale

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