Hello, I was wondering if anyone could help me alter this code so that when I use the "AnalogFrequencyIn" pot, I am able to select a pre-defined scale of notes for each of the steps in the sequencer. Should I be looking at using "case" or an "array" in some way to do this? Any help at all appreciated!
Thanks 
/* ======================================================================
Arduino Punk Console
A simple programmable 8 step tone sequencer
by dano/beavisaudio.com
Revs
-----------------------------------
15 Sept djh initial version
======================================================================*/
// Map all the input and output pins
#define AnalogInFrequency 1
#define AnalogInTempo 2
#define AnalogInDuration 0
#define DigitalOutSignal 11
#define DigitalInSwitch0 2
#define DigitalInSwitch1 3
#define DigitalInSwitch2 4
#define DigitalInSwitch3 5
#define DigitalInSwitch4 6
#define DigitalInSwitch5 7
#define DigitalInSwitch6 8
#define DigitalInSwitch7 9
#define DigitalInStartStop 10
#define DigitalOutLED 12
// Set up the array for each step
int steps[] = {100,120,140,160,180,200,220,240};
// misc housekeeping
int duration = 50;
int pitchval = 1;
int fPlayMode = true;
int lastPushedStep = -1;
// Initialize the tempo
int tempo = 100;
void setup()
{
// setup pin modes (Digital pins are input by default, but
// I like to set 'em explicitly just so the code is clear.
pinMode (DigitalInSwitch0, INPUT);
pinMode (DigitalInSwitch1, INPUT);
pinMode (DigitalInSwitch2, INPUT);
pinMode (DigitalInSwitch3, INPUT);
pinMode (DigitalInSwitch4, INPUT);
pinMode (DigitalInSwitch5, INPUT);
pinMode (DigitalInSwitch6, INPUT);
pinMode (DigitalInSwitch7, INPUT);
pinMode (DigitalInStartStop, INPUT);
pinMode (DigitalOutSignal, OUTPUT);
pinMode (DigitalOutLED, OUTPUT);
// setup comms for the LCD display
Serial.begin(9600);
StartupMessage();
}
void StartupMessage()
{
clearLCD();
Serial.print ("BEAVIS: Arduino");
delay(300);
Serial.print (254, BYTE);
Serial.print (192, BYTE);
Serial.print ("Punk Console!");
delay (2000);
clearLCD();
Serial.print ("Beavis: APC");
}
void clearLCD()
{
Serial.print(254, BYTE);
Serial.print(1, BYTE);
}
void loop()
{
// Main sequence loop
for (int i=0; i<8; i++)
{
// Are we playing or stopping?
fPlayMode = digitalRead (DigitalInStartStop);
digitalWrite (DigitalOutLED, HIGH);
// Check the Hardware
readSwitches();
readPots();
// update the display
updateDisplay();
// Make the noise
if (fPlayMode)
{
freqout (steps[i], duration);
}
digitalWrite (DigitalOutLED, LOW);
// Pause between steps
delay (tempo);
}
}
void updateDisplay()
{
Serial.print (254, BYTE);
Serial.print (192, BYTE);
Serial.print ("T:");
Serial.print (tempo);
Serial.print (" d:");
Serial.print (duration);
if (lastPushedStep != -1)
{
Serial.print ("*");
Serial.print (lastPushedStep);
}
}
// Read the current values of the pots, called from the loop.
void readPots ()
{
tempo = (analogRead (AnalogInTempo) * 1.9);
duration = (analogRead (AnalogInDuration));
}
// Read the current values of the switches and
// if pressed, replace the switch's slot frequency
// by reading the frequency pot.
void readSwitches()
{
// reset last pushed button number
lastPushedStep = -1;
// check switch 0, if pressed, get the current freq into step 0, etc. etc.
if (digitalRead (DigitalInSwitch0) == HIGH)
{
steps[0] = analogRead(AnalogInFrequency);
lastPushedStep = 1;
}
else if (digitalRead (DigitalInSwitch1) == HIGH)
{
steps[1] = analogRead(AnalogInFrequency);
lastPushedStep = 2;
}
else if (digitalRead (DigitalInSwitch2) == HIGH)
{
steps[2] = analogRead(AnalogInFrequency);
lastPushedStep = 3;
}
else if (digitalRead (DigitalInSwitch3) == HIGH)
{
steps[3] = analogRead(AnalogInFrequency);
lastPushedStep = 4;
}
else if (digitalRead (DigitalInSwitch4) == HIGH)
{
steps[4] = analogRead(AnalogInFrequency);
lastPushedStep = 5;
}
else if (digitalRead (DigitalInSwitch5) == HIGH)
{
steps[5] = analogRead(AnalogInFrequency);
lastPushedStep = 6;
}
else if (digitalRead (DigitalInSwitch6) == HIGH)
{
steps[6] = analogRead(AnalogInFrequency);
lastPushedStep = 7;
}
else if (digitalRead (DigitalInSwitch7) == HIGH)
{
steps[7] = analogRead(AnalogInFrequency);
lastPushedStep = 8;
}
}
//freqout code by Paul Badger
// freq - frequency value
// t - time duration of tone
void freqout(int freq, int t)
{
int hperiod; //calculate 1/2 period in us
long cycles, i;
// subtract 7 us to make up for digitalWrite overhead - determined empirically
hperiod = (500000 / ((freq - 7) * pitchval));
// calculate cycles
cycles = ((long)freq * (long)t) / 1000; // calculate cycles
for (i=0; i<= cycles; i++)
{ // play note for t ms
digitalWrite(DigitalOutSignal, HIGH);
delayMicroseconds(hperiod);
digitalWrite(DigitalOutSignal, LOW);
delayMicroseconds(hperiod - 1); // - 1 to make up for fractional microsecond in digitaWrite overhead
}
}
I'm afraid I don't have the programming skills. Any further help much appreciated