keypad interrupt handling esp-idf style and with only one ISR

https://github.com/espressif/esp-idf/blob/master/examples/peripherals/touch_pad_interrupt/main/tp_interrupt_main.c

src/keyboard.cpp

@@ -1,3 +1,12 @@
+#include <stdio.h>
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "esp_log.h"
+
+#include "driver/touch_pad.h"
+#include "soc/rtc_cntl_reg.h"
+#include "soc/sens_reg.h"
+
 #include "Arduino.h"
 #include "keyboard.h"
 
@@ -6,64 +15,56 @@ using namespace std;
 Keyboard::Keyboard() {
 }
 
-void gotTouch0() {
-  touchDetected[0] = true;
-}
-void gotTouch1() {
-  touchDetected[1] = true;
-}
-void gotTouch2() {
-  touchDetected[2] = true;
-}
-void gotTouch3() {
-  touchDetected[3] = true;
-}
-void gotTouch4() {
-  touchDetected[4] = true;
-}
-void gotTouch5() {
-  touchDetected[5] = true;
-}
-void gotTouch6() {
-  touchDetected[6] = true;
-}
-void gotTouch7() {
-  touchDetected[7] = true;
-}
-void gotTouch8() {
-  touchDetected[8] = true;
-}
-void gotTouch9() {
-  touchDetected[9] = true;
+/*
+  Handle an interrupt triggered when a pad is touched.
+  Recognize what pad has been touched and save it in a table.
+  https://github.com/espressif/esp-idf/blob/master/examples/peripherals/touch_pad_interrupt/main/tp_interrupt_main.c
+ */
+static void tp_example_rtc_intr(void *arg) {
+ uint32_t pad_intr = READ_PERI_REG(SENS_SAR_TOUCH_CTRL2_REG) & 0x3ff;
+ uint32_t rtc_intr = READ_PERI_REG(RTC_CNTL_INT_ST_REG);
+ //clear interrupt
+ WRITE_PERI_REG(RTC_CNTL_INT_CLR_REG, rtc_intr);
+ SET_PERI_REG_MASK(SENS_SAR_TOUCH_CTRL2_REG, SENS_TOUCH_MEAS_EN_CLR);
+
+  if (rtc_intr & RTC_CNTL_TOUCH_INT_ST) {
+    for (int i = 0; i < TOUCH_PAD_NUM; i++) {
+      if ((pad_intr >> i) & 0x01) {
+        s_pad_activated[i] = true;
+      }
+    }
+  }
 }
 
 bool Keyboard::getTouchDetected(uint8_t pad) {
-  bool res = touchDetected[pad];
-  touchDetected[pad] = false;
+  bool res = s_pad_activated[pad];
+  s_pad_activated[pad] = false;
   return res;
 }
 
 void Keyboard::init() {
-  threshold[0] = 40;
+  touch_pad_init();
+
+  Serial.println("touchpad values:");
+  for (int i=0; i<TOUCH_PAD_NUM; i++) {
+    uint16_t touch_value;
+    touch_pad_read((touch_pad_t)i, &touch_value);
+    Serial.println(touch_value, DEC);
+  }
+  // set thresholds // ToDo: don't hardcode thresholds
+  threshold[0] = 500;
   threshold[1] = 0;
   threshold[2] = 0;
-  threshold[3] = 40;
-  threshold[4] = 40;
-  threshold[5] = 40;
-  threshold[6] = 40;
-  threshold[7] = 40;
-  threshold[8] = 20;
-  threshold[9] = 20;
-  for (int i=0; i<=9; i++) touchDetected[i] = false;
-  touchAttachInterrupt(T0, gotTouch0, threshold[0]);
-//  touchAttachInterrupt(T1, gotTouch1, threshold[1]); // GPIO_00 not usable on dev board
-//  touchAttachInterrupt(T2, gotTouch2, threshold[2]); // GPIO_02 not usable on dev board
-  touchAttachInterrupt(T3, gotTouch3, threshold[3]);
-  touchAttachInterrupt(T4, gotTouch4, threshold[4]);
-  touchAttachInterrupt(T5, gotTouch5, threshold[5]);
-  touchAttachInterrupt(T6, gotTouch6, threshold[6]);
-  touchAttachInterrupt(T7, gotTouch7, threshold[7]);
-  touchAttachInterrupt(T8, gotTouch8, threshold[8]);
-  touchAttachInterrupt(T9, gotTouch9, threshold[9]);
+  threshold[3] = 666;
+  threshold[4] = 700;
+  threshold[5] = 700;
+  threshold[6] = 800;
+  threshold[7] = 800;
+  threshold[8] = 170;
+  threshold[9] = 350;
+  for (int i=0; i<TOUCH_PAD_NUM; i++) touch_pad_config((touch_pad_t)i, threshold[i]);
+
+  // interrupt handler
+  touch_pad_isr_handler_register(tp_example_rtc_intr, NULL, 0, NULL);
 }
 

src/keyboard.h

@@ -1,10 +1,15 @@
 #ifndef _KEYBOARD_H
 #define _KEYBOARD_H
 
-#include "Arduino.h"
+#include "driver/touch_pad.h"
+
+#define TOUCH_PAD_NUM 10
+
+static bool s_pad_activated[TOUCH_PAD_NUM];
+
+static bool touchDetected[TOUCH_PAD_NUM];
+static uint16_t threshold[TOUCH_PAD_NUM];
 
-static bool touchDetected[10];
-static uint8_t threshold[10];
 
 class Keyboard {
   public:

src/main.cpp

@@ -18,13 +18,14 @@ void setup()
 {
   // initialize LED digital pin as an output.
   pinMode(LED_PIN, OUTPUT);
-  keyboard.init();
   Serial.begin(115200);
   Serial.println("-------------------------------------");
   Serial.print("Soundboard v.");
   Serial.println(VERSION);
   Serial.println("https://dev.xd0.de/hendrik/soundboard");
   Serial.println("-------------------------------------");
+
+  keyboard.init();
 }
 
 void loop()