fbiego / cst816s

An Arduino library for the Hynitron CST816S capacitive touch screen IC

CST816S

An Arduino library for the CST816S capacitive touch screen IC

cst816s's Issues

Screen Size

Hi, where should I define the screen size?

CST816S - Data Reference

Hello,

Do you have the CST816S Data Reference document which lists all the addresses and technical information ?

Also is the CST816S the same as the CST816D ?

We need to increase the swipe detection response.

Thanks

Maybe the location of touch is not correct

My touch chip is CST816T.
I tried this library, it works well, except that the y position is always less than 255.

According to the datasheet, maybe x and y should be:

data.x = data_raw[2] & 0xF;
data.x = (data.x << 8) + data_raw[3];

data.y = data_raw[4] & 0xF;
data.y = (data.y << 8) + data_raw[5];

Does it also work with CST816T?

I hope it is ok to write my question under the issue field. Has someone tried this library with CST816T chips?
With best regards!

Compilation errors with ESP32-C3 and ESP8266

I think it has some issues.
Tried to compile with Arduino-IDE 2.2,1

Here is the compilation errors when I try to compile for ESP32C3.
Also there are some compilation errors with ESP8266..

/home/death/Arduino/libraries/CST816S/CST816S.cpp: In member function 'uint8_t CST816S::i2c_read(uint16_t, uint8_t, uint8_t*, uint32_t)':
/home/death/Arduino/libraries/CST816S/CST816S.cpp:173:38: error: call of overloaded 'requestFrom(uint16_t&, uint32_t&, bool)' is ambiguous
   Wire.requestFrom(addr, length, true);
                                      ^
In file included from /home/death/Arduino/libraries/CST816S/CST816S.cpp:26:
/home/death/.arduino15/packages/esp32/hardware/esp32/2.0.11/libraries/Wire/src/Wire.h:119:12: note: candidate: 'size_t TwoWire::requestFrom(uint16_t, size_t, bool)'
     size_t requestFrom(uint16_t address, size_t size, bool sendStop);
            ^~~~~~~~~~~
/home/death/.arduino15/packages/esp32/hardware/esp32/2.0.11/libraries/Wire/src/Wire.h:120:13: note: candidate: 'uint8_t TwoWire::requestFrom(uint16_t, uint8_t, bool)'
     uint8_t requestFrom(uint16_t address, uint8_t size, bool sendStop);
             ^~~~~~~~~~~
/home/death/.arduino15/packages/esp32/hardware/esp32/2.0.11/libraries/Wire/src/Wire.h:121:13: note: candidate: 'uint8_t TwoWire::requestFrom(uint16_t, uint8_t, uint8_t)'
     uint8_t requestFrom(uint16_t address, uint8_t size, uint8_t sendStop);
             ^~~~~~~~~~~
/home/death/.arduino15/packages/esp32/hardware/esp32/2.0.11/libraries/Wire/src/Wire.h:122:12: note: candidate: 'size_t TwoWire::requestFrom(uint8_t, size_t, bool)'
     size_t requestFrom(uint8_t address, size_t len, bool stopBit);
            ^~~~~~~~~~~
/home/death/.arduino15/packages/esp32/hardware/esp32/2.0.11/libraries/Wire/src/Wire.h:124:13: note: candidate: 'uint8_t TwoWire::requestFrom(uint8_t, uint8_t, uint8_t)'
     uint8_t requestFrom(uint8_t address, uint8_t size, uint8_t sendStop);
             ^~~~~~~~~~~
/home/death/.arduino15/packages/esp32/hardware/esp32/2.0.11/libraries/Wire/src/Wire.h:126:13: note: candidate: 'uint8_t TwoWire::requestFrom(int, int, int)'
     uint8_t requestFrom(int address, int size, int sendStop);
             ^~~~~~~~~~~

exit status 1

Compilation error: exit status 1

For fixing it, you should use size_t at wire definitions...

    uint8_t i2c_read(uint16_t addr, uint8_t reg_addr, uint8_t * reg_data, size_t length);
    uint8_t i2c_write(uint8_t addr, uint8_t reg_addr, const uint8_t * reg_data, size_t length);

Bugs/issues

So I've been testing this on an RP2040 and also ESP32....

The Double Tap (click) never triggers, no matter how fast or slow I try tapping the screen, it only ever registers a SINGLE tap

Touch points is always 1 - I'm not entirely sure what this is supposed to do, but it's just always 1

Event - from the library comments I'm assuming this is meant to allow you to differentiate between touching and releasing but it just doesn't really work. when touching, it's 2, when I remove my finger after a swipe for example, 95% of the time it remains 2. Rarely it will show 1 which Is what I would expected when removing my finger / exiting the screen

This is a great start at a library, but it really isn't hugely useful in it's current state because of the inconsistencies etc

How does one deduce when an action has been completed RELIABLY? Again, Double Tap/Click is never recognised either

FunctionalInterrupt

hello ,
On compiling the code in arduino , i Get this error
Arduino: 1.8.16 (Windows 7), Board: "Arduino Uno"
In file included from C:\Users\vishal\Documents\Arduino\libraries\CST816S-1.1.0\CST816S.cpp:27:0:

C:\Users\vishal\Documents\Arduino\libraries\CST816S-1.1.0/FunctionalInterrupt.h:7:10: fatal error: functional: No such file or directory

#include "functional"

      ^~~~~~~~~~~~

compilation terminated.

exit status 1

Error compiling for board Arduino Uno.

This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.

Gesture function always returns none.

I'm sure I'm missing something, but I can't get any gesture information.
No matter what I do on the screen gesture always returns "NONE".