START QTouch troubles

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I got started with the QTouch example in START for my SAMD10 Xplained Mini board. In the documentation folder in the project is says to refer to this document for how to use the QTouch API: http://www.atmel.com/Images/Atme... but this is definitely describing something other than what was downloaded. I found this page (https://www.microchip.com/Develo...) but it is no help because...which of these documents should I be looking at? There's a very 1 released after a version 5. There's a SAMD document, but that's specific to safety applications.

 

I found this one that I think is right? https://ww1.microchip.com/downlo... Is everything configured 100% with defined vars, almost no function calls?

 

The next problem I am having is with the Data Visualizer. I see the mEDBG COM interface in the Data Visualizer in Microchip Studio, and I selected the datastreamer folder, but it tries every baud rate and says "Protocol not detected on COMX." The self-cap sensor and LED are working properly.

 

The last bit if missing documentation is how to tune QTouch for proximity sensors. I have found tons of documentation on how to physically design proximity sensors for the PTC, but I have found nothing about how to best tune and adjust QTouch for proximity sensors. Do I just treat it is a "button" and tune it manually until it seems to work? Is there another way to get data out of it to tune it since the Data Visualizer doesn't seem to work?

 

Thanks!

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Well, it seems that a proximity sensor is just a button with high gain according to here: https://microchipdeveloper.com/t...

 

Though it also words it as "Proximity could be created" as if it is not recommended, but there are other docs describing how to design proximity pads and proximity rings on some eval boards. I suppose I suppose I should look at example code for those.

Last Edited: Fri. Apr 9, 2021 - 04:28 AM
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OK,

 

So the Datastreamer issue was definitely an issue with the Xplained Mini board's USB serial. Connecting to an external serial converter got it to work reliably. I am able to reproduce this issue on all 3 boards I bought and with GCC/OpenOCD, MPLab, and Microchip Studio. Attached are some screenshots. The built-in serial on top, and the external on the bottom. This is using PA10/PA11. It sounds like this is maybe a problem with many of the Xplained boards of similar design given the other forum posts about it. I opened a support ticket about it but who knows if I will get a response.

 

Everything does seem to be configured with define calls in touch.h. Is there a way to configure the thresholds and analog gains programmatically?

 

I was able to make a quick demo with 3 proximity sensors, but they are in need of the active guard or Driven Shield feature. This wiki page (https://microchipdeveloper.com/touch:guide-for-timer-based-driven-shield-on-sam-devices) says that this can be done with a timer since the SAM chips don't do it in the PTC. But It is entirely grayed out in START even when selecting pins all with the same TCC or TC. More pictures attached of that. When I switch to another SAM chip (i.e. SAMC21), the checkbox works. I cannot find any documentation stating which chips support or don't support the timer-/PWM-based guard. It seems all of the SAM chips with PTC should be able to do this (it's just a timer on a pin, right?). I also submitted a support case about this.

 

I got an email that I can call Microchip about my support cases. In anyone else's experience does that yield a result or is it just to leave a voice message?

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A follow up question would also be... is there a way to use QTouch without START? Sure it makes a "configurable" touch.h but it only populates it with the features that you enable online, and I find myself refreshing the page or running into freezes/errors way to often.