From 026937393bb45084a0fa33a643d3411ff5c1be63 Mon Sep 17 00:00:00 2001
From: Fisch <interfisch@gmx.net>
Date: Wed, 22 Jan 2020 21:43:53 +0100
Subject: [PATCH] add touchcontroller code for arduino pro mini

---
 touchcontroller/touchcontroller.ino | 87 +++++++++++++++++++++++++++++
 1 file changed, 87 insertions(+)
 create mode 100644 touchcontroller/touchcontroller.ino

diff --git a/touchcontroller/touchcontroller.ino b/touchcontroller/touchcontroller.ino
new file mode 100644
index 0000000..0874cd3
--- /dev/null
+++ b/touchcontroller/touchcontroller.ino
@@ -0,0 +1,87 @@
+
+#define INPUTS 8
+byte touchOut=0; //binary encoded sensors
+uint16_t rawIn[INPUTS];
+
+uint16_t countedLow[INPUTS]; //count the times input was below threshold (touched)
+#define TOUCHTHRESHOLD 300 //below which value input counts as touched
+#define COUNTEDLOWTHRESHOLD 10 //how many times input has to be sampled as low in a row to count as real touch. 
+// Inputdelay is given by: COUNTEDLOWTHRESHOLD*ADCREADINTERVAL
+
+long last_adcmicros=0;
+#define ADCREADINTERVAL 2000 //in microseconds. interval to read all adc values
+
+boolean inputchangeFlag; //flag to update keypress
+long last_send=0;
+#define MINIMUMSENDDELAY 10 //in milliseconds. minimum delay between serial sends
+
+void setup() {
+  pinMode(A0, INPUT_PULLUP);
+  pinMode(A1, INPUT);
+  pinMode(A2, INPUT_PULLUP);
+  pinMode(A3, INPUT_PULLUP);
+  pinMode(A4, INPUT_PULLUP);
+  pinMode(A5, INPUT_PULLUP);
+  pinMode(A6, INPUT_PULLUP);
+  pinMode(A7, INPUT_PULLUP);
+  Serial.begin(115200);
+}
+
+void loop() {
+  long loopmillis=millis();
+
+  // ## Sampling and Touch Filtering ##
+  if (micros()-last_adcmicros>=ADCREADINTERVAL) 
+  {
+    last_adcmicros=micros();
+    //Sample all analog Inputs
+    rawIn[0]=analogRead(A0);
+    rawIn[1]=analogRead(A1);
+    rawIn[2]=analogRead(A2);
+    rawIn[3]=analogRead(A3);
+    rawIn[4]=analogRead(A4);
+    rawIn[5]=analogRead(A5);
+    rawIn[6]=analogRead(A6);
+    rawIn[7]=analogRead(A7);
+    //Serial.print(analogRead(A1));
+    //Serial.print(": ");
+    //Serial.println(micros()-mic);
+
+    for (uint8_t i=0;i<INPUTS;i++){ //for all inputs
+      if (rawIn[i]<=TOUCHTHRESHOLD) { //touch detected (input low at this sample)
+        countedLow[i]++; //increase counter
+        if (countedLow[i]>=COUNTEDLOWTHRESHOLD) { //upper limit
+          countedLow[i]=COUNTEDLOWTHRESHOLD; //upper limit. prevent overflow
+          inputchangeFlag=true; //flag to update keypress
+        }
+      }else{ //released or not pressed hard enough
+        countedLow[i]=0; //reset counter
+        inputchangeFlag=true; //flag to update keypress
+      }
+    }
+    
+  }
+
+  // ## Send to Raspberry ##
+  if (inputchangeFlag) { //something changed
+    if (loopmillis-last_send>MINIMUMSENDDELAY) //delay between last send long enough
+    { 
+      touchOut = 0; //reset bits
+      for (uint8_t i=0;i<INPUTS;i++){ //for all keys
+        if (countedLow[i]>=COUNTEDLOWTHRESHOLD) { //key pressed/touched
+          touchOut^=1<<i;
+          //Serial.print("1");
+        }//else{
+          //Serial.print("0");
+        //}
+      }
+      //Serial.println(touchOut, BIN);
+      //Serial.println();
+      Serial.write(touchOut);
+      last_send=loopmillis;
+      inputchangeFlag=false; //clear Flag
+    }
+  }
+
+  
+}