Re: Waking up a serial port

On Wed, 19 Mar 2025 01:46:23 -0000 (UTC), bp@www.zefox.net wrote:

Theo <theom+news@chiark.greenend.org.uk> wrote:

 
I'm not seeing an MCU, although it could be underneath or on another board.

>
It turns out there is an smd package with at least 40 pins on the
perpendicular daughter board at the lower of the photo at
http://www.zefox.net/~bp/ampinvt/2nd_inverter/board_photos/IMG_0007.JPG
It's only about 10 mm square, so any markings are going to be tiny.

10 mm body might be a QFP64 package.
<https://www.amazon.com/programming-machine-Size10x10mm-12x12mm-FPQ-64-0-5-06/dp/B0757JNQR4>

Unfortunately it's on the side that can't be seen in the photo. It's
mounted diagonally, as one sees on images of SBCs. I've tried to get
a look at the package markings but can't make them out vi a dental
mirror, too much stuff in the way. The packaging is rather tight, so
improving the view won't be easy 8-(
>
Obviously it might help to identify the device. Then again, it might not....
I'll try to figure out how to get a good look. Something like a camera
periscape the size of a pencil would be about right 8-)

Try an endoscope camera:
<https://www.ebay.com/sch/i.html?_nkw=endoscope+camera&LH_PrefLoc=1>
They comes in 5.5, 6, 7 or 8mm dia probes.  7mm seems to be a good
compromise between viewing angle, depth of field and illumination.

I'm hesitant to
start taking things apart because the device is still usable, if not
entirely perfect.

If you leave it torn apart, you'll eventually lose some parts or
hardware which potentially will make it useless.  That's what recently
happened to me with a Chinese 12VDC to 115VAC power supply.  Best to
make your decision fairly soon. 


--
Jeff Liebermann                 jeffl@cruzio.com
PO Box 272      http://www.LearnByDestroying.com
Ben Lomond CA 95005-0272
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