On Thu, 16 Jul 2020 19:24:36 +0200, "R.Wieser" 
declaimed the following:

>Indeed.   Especially the USB pins, and asked myself if I could perhaps wire
>it up to an USB connector - only to realise that if the firmware is not
>written for it neither the SPI nor the USB pins will do anything.   Heck,
>those hardware parts might not even be on the used chip.
>

 Based upon the link that suggested uploading a more capable firmware, I
suspect the chip does have all the parts for that pinout. The SPI pins
appear to be used for firmware updating.

>Although I would gladly accept that (would make my life /that/ much easier),
>its not what the specs to the HC-05 breakout board says : a 3.6v minimum
>voltage.   But, I don't know why they say that*, as the HC-05 module itself
>will, according to the PDF, happily work with a supply as low as 1.8 volts

 Partly, I suspect, as any on-board voltage regulator will consume some
of the input voltage just to ensure a stable 3.3V output. The second reason
may be that MAX3232 (or was that 2323 ). The double ended voltage
multiplier (to get both +12 and -12 for true RS-232) may require at least
some higher level to function.

>
>Could you post the direct link to that image ?
>
 I'd like to, but the image selection appears to be handled by Amazon
Javascript on the page, as the mouse passes over them -- the URL doesn't
change. I see, on the left:

Top view diagonal of board with jumper at lower right,  with small
schematic bottom left and module dimension diagram top right.

Diagonal view top with jumper at lower left, no auxiliary diagrams

Top down view, jumper on left

Diagonal view bottom, jumper lower right

Schematic only

Module dimensions only


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


--
 Wulfraed                 Dennis Lee Bieber         AF6VN
 wlfraed@ix.netcom.com    http://wlfraed.microdiversity.freeddns.org/

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