Dennis,

> Partly, I suspect, as any on-board voltage regulator will consume
> some of the input voltage just to ensure a stable 3.3V output.

Yes.  0.3 volts.  At least, thats the difference between the minimum allowed
supplied and the I/O voltage.   Supplying 3.3v should drop the I/O voltage
to 3.0 volt, which should be plenty enough for an input pin of a 3.3v MCU*.

That is, assuming that the voltage regulator itself doesn't throw a wrench
into it (will go into  a kind of "pass thru" mode when it gets a too-low
voltage).

*on the other hand, having an output pin supply 3.3 to an input-pin of
device that runs on 3.0 volts could create problems in regard to possible
present clamping diodes.

> The page source is over 18000 lines (about half are blank lines),
> most is Javascript. The thumbnail for the image is at line 9720,

My thanks for going thu it.   Thats really a cr*pload.

> but I don't know how to go from
>
https://images-na.ssl-images-amazon.com/images/I/41fnAp8oUUL._SX38_SY50_CR,0,0,
38,50_.jpg
> to the full size version. I suspect it's coded into that file name, and
> the server parses it to provide the image as the mouse moves over
> the thumbnail.

I took a chance and just removed everything from the second-to-last dot upto
the ".jpg" extension.   I got a 500x500 image back, which stil is isn't
perfect but better readable than what I had.

Regards,
Rudy Wieser

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