Improve W1209 ease of use

[TG9541]

Several users have had difficulties getting the W1209 serial communication to work, e.g.:

• https://hackaday.io/project/16097-eforth-for-cheap-stm8s-gadgets/discussion-90018
• http://forum.hobbycomponents.com/viewtopic.php?f=73&t=1900&p=5498#p5498
  This issue should improve the "user experience".

Issue #41 enables using e4thcom (and regular serial terminal programs) more easily. Consistent documentation, board support, and decisions about "phasing out" sensor header communication shall be taken here.

[TG9541]

Issue #41 is now closed. e4thcom works fine using PC4/PC5 (keys "+" and "-"), and using the board keys in interactive mode works, too.

[TG9541]

@barewires: according to the hobbycompents W1209 STM8EF forum thread your experience with the sensor header serial interface were, well, not good. What's your opinion about the new solution?

v2.2.13.snapshot contains the W1209-FD variant.

[alfredluca]

I tested the W1209-FD.ihx binary and wrote a "how-to":

How-To:

• get a W1209, erase the chip if necessary
• flash the W1209-FD.ihx binary
• connect the serial interface (+key pin near LED display -> TxD, -key -> RxD)
• use terminal program "9600/N/8/1"

It's as easy as using a STM8S103F3 breakout board!

[TG9541]

Thanks for the feedback so far!

I updated the Wiki.

[barewires]

Great work Thomas! I had put the W1209 on the back burner concentrating on the MINDEV, RCWL-0516 Cat Detector and HC12 comms. My only thought is grounding the TX/RX and debounce. Still a much appreciated update.

[TG9541]

Hi Barewires, thanks for the feedback!

I read your latest hobbycomponents forum post - together with Alfredo's post it makes a good account of what can go wrong, and why independent testing is important. I hope that we're on track now. Thanks a lot :-)

I also updated the Wiki (please refer to the link in my previous comment). It would be nice if you could comment on it's usefulness.

You mention debouncing measures for RX/TX. Did you observe communication errors?
Can you propose a circuit (e.g. RC)?

PS: it's great that Picocom works. That's a good starting point for using e4thcom (it now has a STM8EF plugin, and it should work on the Raspberry Pi). Here is a small demo what it can do to make an STM8EF programmer's life easier.

[TG9541]

Let's then use the "full duplex" option as the default. The docs will be changed accordingly which, I guess, will make new users life much easier.