update

source/old testing stuff/midi_in_out_softwareserial/midi_in_out_softwareserial.ino

@@ -0,0 +1,62 @@
+#include <Wire.h>
+#include <SoftwareSerial.h>
+
+#define IOPOLA   0x02
+#define GPPUA   0x12
+#define BIT_IS_SET(i, bits)  (1 << i & bits)
+
+SoftwareSerial MIDI(10,11);
+
+boolean button[8];
+
+void setup()  
+{
+  //printing baudrate
+  Serial.begin(9600);
+  MIDI.begin(31250);
+  Wire.begin();
+   Wire.beginTransmission(0x20);
+  Wire.write(0x12); // set MCP23017 memory pointer to GPIOB address
+  Wire.write(0xFF); //PULLUP
+  Wire.endTransmission();
+}
+
+void loop()
+{
+  Wire.beginTransmission(0x20);
+  Wire.write(0x12); // set MCP23017 memory pointer to GPIOB address
+  Wire.endTransmission();
+  Wire.requestFrom(0x20, 1); // request one byte of data from MCP20317
+  int inputs = Wire.read();
+  delayMicroseconds(10);
+  //check if button is pressed
+  
+  int i;
+  for(i=0;i<8;i++) {
+    if (BIT_IS_SET(i,inputs)) {
+      if(!button[i]) {
+        button[i] = true;
+        midiSignal(144,60+i,115);
+      }
+    } else {
+      if(button[i]) {
+        button[i] = false;
+        midiSignal(128,60+i,0);
+      }
+    }
+  }  
+}
+
+//send MIDI signal through softwareserial
+void midiSignal(byte b1, byte b2, byte b3) {
+  Serial.print(b1);
+  Serial.print(" ");
+  Serial.print(b2);
+  Serial.print(" ");
+  Serial.print(b3);
+  Serial.print(" ");
+  Serial.println();
+  MIDI.write(b1);
+  MIDI.write(b2);
+  MIDI.write(b2);
+}