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Subject: Re: Atompro timing anomolies....

From: "djbrow54" <davebr@...>
Date: 2007-01-24

The resonator is reasonably sized compared to the other components and
the landing pads are long enough that I think you could even solder
discrete parts to it. I'm a bit perplexed as to how to get the
resonator off there without specialized SMT desoldering equipment.
One thought I had was to grind it off with a dremel tool and then
unsolder each pad and hopefully not destroy the module. Or perhaps
with enough heat on top of the resonator the three lower pads would
desolder. However, I'm not prepared to try. I may ask one of the
techs at work how it is done. After that it looks easy enough but you
are correct - there are some really fine pitched parts on that module.

Another thought (and I'm looking at my AtomPro28, not the 24) is that
one clock run is reasonably long along the side. The other goes to a
feedthrough right above the resonator. I suppose if you are lucky,
the feedthrough "could" be the pin that you would leave open and the
long run "could" be one that you could cut and feed the clock into.
It would be a matter of tracing the runs out.

Dave

--- In ComputerVoltageSources@yahoogroups.com, "drmabuce" <drmabuce@.
..> wrote:
>
> Hi Dave
> thanks for the exploration
> i took a look at processor pins 9&10 on my PSIM PCB and ... boy! you
> ain't a-kiddin' about the 'not for the faint-of-heart'!
> Like most human-sized, 70's wire-twisters, (with half-century old
> eyesight and a propensity to sneeze SOIC components off the
workbench)
> ...i'm not terribly comfortable tearing into surface-mount under
good
> conditions but this layout is tight as a... well...
> (this is an all ages site so... let's just say it's TIGHT)
> hmmmmmm, so far i looks to me like shopping list for external
> processor clocking will include, at a minimum, expert SOIC component
> removal skills/tools, flying wires off the BasicAtom and cancelling
> the modularity that allows a BasicAtom swap....
> and that list excludes the design of a module that caters to the
> H8/3664's clock requirements and ostensibly some arbitrary form of
> compatibility with an external standard....
>
> That shopping list will require a very motivated buyer
> and...
> it looks like it would score just about the same pain in the ass
> index as a workaround-software scheme , ie: trying to , as Senor
> Brombaugh put it, implement some sort of software PLL.
>
> yuck...
> even the 'elegant' solutions are inelegant
> (and brute force will be expensive)
>
> another point for Murphy's law!
> -doc