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bitbank2 / bb_captouch

An ESP32/Arduino library to talk to CST820, FT6x36 and GT911 capacitive touch sensors (auto-detects)
Apache License 2.0
20 stars 7 forks source link

CST820 datasheet? #5

Closed chupocro closed 2 months ago

chupocro commented 2 months ago

Hi,

I was looking for but cound't even find a CST820's manufacturer, let alone a datasheet. Where did you find it to write the library?

Regards

bitbank2 commented 2 months ago

I don't have access to the datasheet. Most cap touch sensors work the same way. I was able to make it work by looking at the register positions in someone else's code.

chupocro commented 2 months ago

I have a source code for CST820 driver from the documentation of JC2432W328 display I mentioned here:

https://github.com/witnessmenow/ESP32-Cheap-Yellow-Display/discussions/200#discussioncomment-10078820

But it could be seen from the code the implemented functionality is only partial, that's why I've been looking for the datasheet.

The author of this page mentioned your library and the library from some display's documentation too and he said:

(translated from Japanese)

I found two types of CST820 libraries used for the touch panel. One is published as a library called bb_captouch. The other is included in the 24C demo program, cst820.cpp. Both support single-point touch, but other operations are unclear. bb_captouch supports two-point touch, but stops about 100ms after touch.

  • Some initialization is probably required, but the method written in cst820.cpp does not work.
  • cst820.cpp has a description of gestures, but this does not work either.
  • I guess the important parts will not be disclosed unless you sign a contract. I guess there's no other way.

Maybe the author of the code you used to write the library has the datasheet?

bitbank2 commented 2 months ago

Not sure what to say. It's not on my to-do list at the moment. If you find the info, please let me know.