Capture off screen touch button events

rashedtalukder · October 19, 2021, 7:09pm

I’m using the M5Stack Core2 for AWS, which has a 320x240 pixel screen with a FT6336U touch controller. There are 3 etched circles on the front of the device that go beyond the dimensions of the display itself which can be read by the touch controller. I’ve seen the LVGL ESP32 drivers, which has a default option to support the hardware. I can see the touch inputs (printed X-Y coordinates) from ft6x36_read() for the button area.

I have tried creating 3 button widgets that are positioned in the off-screen areas where the etched circles are, however, I don’t see the button event getting triggered. Is there a relatively simple way this can work that I haven’t been able to dig up?

rashedtalukder · October 21, 2021, 3:18pm

I submitted a PR a little bit after posting this question since it didn’t look like this was feasible. This problem is unique to the M5Stack Core2 and Core2 for AWS IoT EduKit. Hopefully the PR gets merged so the repository could be submoduled from upstream instead of a fork:

github.com/lvgl/lvgl_esp32_drivers

Add touch input values to an accessible FreeRTOS queue

lvgl:master ← rashedtalukder:master

opened 12:42AM - 20 Oct 21 UTC

rashedtalukder

+46 -20

For applications that might want to read the touch values without creating anoth…er task that is also reading the FT6336U over the i2c bus. This is especially an issue for the M5Stack [Core2 for AWS IoT EduKit](https://shop.m5stack.com/products/m5stack-core2-esp32-iot-development-kit-for-aws-iot-edukit) or standard Core2 that has etched buttons and touch sensing capabilities that are past the bounds of the screen perimeter. Queue was chosen due to their minimal overhead and non-blocking. Directly copied the values to the queue instead of a pointer since the struct size is fairly small. Example Usage: ```C #include "freertos/FreeRTOS.h" #include "freertos/task.h" #include <esp_log.h> #include "ft6x36.h" static const char* TAG = "MAIN"; void button_press_task( void *args ) { ***INITIALIZE EVERYTHING FIRST*** ft6x36_touch_t touch_received; for ( ;; ){ xQueueReceive( ft6x36_touch_queue_handle, &touch_received, 0 ); ESP_LOGI( TAG, "X=%i Y=%i State=%u", touch_received.last_x, touch_received.last_y, touch_received.current_state ); vTaskDelay(pdMS_TO_TICKS(20)); } } void app_main( void ) { xTaskCreatePinnedToCore( button_press_task, "buttonPress", configMINIMAL_STACK_SIZE * 3, NULL, 0, ( TaskHandle_t * ) NULL, 1 ); } ```