Jim,

Thanks for the link.  But look at that pin  description table.   It
doesn't actually *say* anything.

"STATE" "Mode the device is in"

- What "mode" are they talking about ?
- Which pin of the HC-05 module is it connected to ?  (presuming it is)
- Is it a direct connection or does the break-out board have any components
(resistor, diode, etc) in it.  If the latter, for what purpose (what is its
effect).
- In the case its /not/ a direct connection : Which "high" voltage does it
output ?

"EN" "Disables module when LOW"

- Which pin of the HC-05 module is it connected to ?  (presuming it is)
- Is it a direct connection or does the break-out board have any components
(resistor, diode, etc) in it. If the latter, for what purpose (what is its
effect).
- In the case its /not/ a direct connection : Which "high" voltage does it
accept (min and max) ?

You know, the basic stuff.

Really, just mentioning where the STATE and EN pins are connected to on the
HC-05 module would be, to me, way more helpfull.

Furthermore:
- if a low disables the module, how to I enter the "command" mode (so I can
configure it), as my module doesn't have a pushbutton.  ... or did I buy an
intentionally crippled one ?    That would be a bit hard to swallow.

> The photo shows RX/TX at 3.3V logic levels

You mean by way of the silk-screen text ?   Yeah, I noticed.

> Even it has a safety resistor putting another one will very
> probalby be ok - and safe!

Don't be too sure about that: back-current thru such a resistor and the
clamping diodes is known to be problematic (I probably followed the same
thread you mentioned :-) )

> Or buy a little dual 3.3V  5V level shifter to use between
> the device and the MCU

Yeah, I know I can do that.  Together with another 3.3v voltage regulator
(and supporting components) ofcourse.  But thats sheer insanity.

Bottom line: A breakout board which makes it impossible to feed the HC-05
from a 3.3v source (presumably due to a voltage drop in the power
regulator), but which also doesn't seem to have anything for the signal
lines to make it easy to use the HC-05 module on a higher voltage.   Its
almost as if its some kind of intricate joke.

Regards,
Rudy Wieser

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