Alister,

> 1st result when searching for hc05 on google
> https://components101.com/wireless/hc-05-bluetooth-module
> seems pretty straight forward to me

Absolutily !

.... up until the moment you find some more of the same on other webpages,
which mentions that the EN pin just disables the module.  No mentioning of a
datamode there.

Also, my board doesn't have that button shown there.  Should I therefore
presume its crippeled ?  Or does it maybe work differently ?

And by the way: No mentioning of signal levels for/of the EN and STATE pins
anywhere, nor if the breakout board adds tolerance for 5v signals on TX and
RX and perhaps the above two too.

To make things worse: the wiring diagram in the "How to Use the HC-05
Bluetooth module" chapter mentions that the TXD and RXD go to the MCU -
which under the "HC-05 Technical Specifications" might be an Arduino - which
is supposed to run on 5v, and directly connecting the RX pin to one of the
Arduinos pins set to output will likely destroy the 3.3v module.    Either
someone forgot something, or that particular module can handle 5v signals.

Nope sirree, its not as straight forward as you think it is. :-)

Regards,
Rudy Wieser

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