Then I soldered similar circuits to the analog inputs 5, 4, 3, and 2 like I used for the push buttons. 10K resistor pull the input down to the ground. Then the same input is connected to the +5V via a jumper and a 500 ohm resistance. The jumper is then connected to the external connector. By shorting the external connector it works similarly as a push button. If a variable resistor is connected to the external connector then it works as an analog input.

Here is a picture about the board:

Analog inputs and their connections to the back panel

I disassembled the box. Well it is not the best for this project, since it is closing with clips and not screws but it was free so I can live with that. I tried my board into it and found that I have to cut a couple of centimeters from the end of the board.

Here are some pictures about the box and the cut board:

ZIP drive box

Now the board is shorter

As you can see I cut two holes on the side of the box. They are for the external power connector and usb connector of the arduino. I still have to cut a hole for the LCD and drill some holes for the potentiometers and buttons.

I also assembled connectors to the back panel of the box:

Back panel

I soldered jumper cables to the connectors. Two connector is connected to a single jumper cable. The second pins of each connector are connected together and the will be connected to the ground. I also use a jumper cable for that.

When I will get the second potentiometer I will connect its side pins to the corresponding pins on the other potentiometer. The middle pin will be connected to the free wire on the second cable.

I will use the connected potentiometer for setting a treshold value. For instance it can be used for calibrating microphone input. The second potentiometer will be used to input delay values. I will use a precision potentiometer (turns 10x) for that.

Here is a picture of the hardware:

Potentiometer added

I also added the treshold input to the code:

// include the library code:
 #include <LiquidCrystal.h>

 const int numRows = 2;
 const int numCols = 16;

 //Digital pins
 const int lcdBackLightPin = 12;
 const int upButtonPin = 6;
 const int downButtonPin = 5;
 const int setButtonPin = 4;
 const int resetButtonPin = 3;

 //Analog pins
 const int tresholdPin = 0;

 char* mainMenu[]={"start", "delay", "treshold", "test"};
 int mainMenuIndex = 0;
 int mainMenuNextItem = 1;
 int mainMenuItemNum = 4;
 boolean menuUpdate = false;

 int treshold = 0;

 // initialize the library with the numbers of the interface pins
 LiquidCrystal lcd(13, 11, 10, 9, 8, 7);

 void setup() {
   // set up the LCD's number of rows and columns:
   lcd.begin(numRows, numCols);
   lcd.clear();
   lcd.setCursor(0, 0);
   lcd.print(">");
   lcd.setCursor(2, 0);
   lcd.print(mainMenu[mainMenuIndex]);
   lcd.setCursor(2, 1);
   lcd.print(mainMenu[mainMenuNextItem]);
   digitalWrite(lcdBackLightPin, HIGH);

   pinMode(lcdBackLightPin, OUTPUT);
   pinMode(upButtonPin, INPUT);
   pinMode(downButtonPin, INPUT);
   pinMode(setButtonPin, INPUT);
   pinMode(resetButtonPin, INPUT);

 }

 void setTreshold()
 {
   int cursorOn = 1;
   delay(300);

   while(!digitalRead(setButtonPin))
   {
     treshold = analogRead(tresholdPin);
     lcd.clear();
     lcd.setCursor(0, 0);
     lcd.print("Treshold:");
     lcd.setCursor(0, 1);
     if(cursorOn)
     {
       lcd.print("> ");
       cursorOn = 0;
     }
     else
     {
       lcd.print("  ");
       cursorOn = 1;
     }

     lcd.print(treshold);

     delay(300);
   }
 }

 void loop() {
   if(digitalRead(upButtonPin))
   {
     mainMenuIndex++;
     if(mainMenuIndex >= mainMenuItemNum)
     {
       mainMenuIndex = 0;
     }  
     mainMenuNextItem++;
     if(mainMenuNextItem >= mainMenuItemNum)
     {
       mainMenuNextItem = 0;
     }
     menuUpdate = true;
   }
   else if(digitalRead(downButtonPin))
   {
     mainMenuIndex--;
     if(mainMenuIndex < 0)
     {
       mainMenuIndex = mainMenuItemNum - 1;
     }  
     mainMenuNextItem--;
     if(mainMenuNextItem < 0)
     {
       mainMenuNextItem = mainMenuItemNum - 1;
     }
     menuUpdate = true;
   }
   else if(digitalRead(setButtonPin))
   {
     switch(mainMenuIndex)
     {
       /*
       case 0:     
       break;

       case 1:
       break;
       */
       case 2: setTreshold();
         menuUpdate = true;      
       break;
       /*  
       case 3:
       break;

       default:
       */
     }
   }

   if(menuUpdate)
   {   
     lcd.clear();
     lcd.setCursor(0, 0);
     lcd.print(">");
     lcd.setCursor(2, 0);
     lcd.print(mainMenu[mainMenuIndex]);
     lcd.print(" <");
     lcd.setCursor(2, 1);
     lcd.print(mainMenu[mainMenuNextItem]);
     menuUpdate = false;
     delay(300);
   }
 }

After reviewing my half made board and my last post I found that I have the following pins free:

Digital I/O:  2, 1, 0

Analog input: 0, 1, 2, 3, 4, 5

I will use the digital pins as digital outputs.

The first two analog pins (0 and 1) will be used for built in potentiometers.

The analog 2 and 3 pins will be configured as digital inputs and they will have similar circuits like the push buttons. The only difference is that we will replace the button with a connector.

The analog 4 and 5 will be directly connected to connectors.

Now, I have plan Lets solder!

// include the library code:
 #include <LiquidCrystal.h>

 const int numRows = 2;
 const int numCols = 16;

 const int lcdBackLightPin = 12;
 const int upButtonPin = 6;
 const int downButtonPin = 5;
 const int setButtonPin = 4;
 const int resetButtonPin = 3;

 char* mainMenu[]={"start", "delay", "test"};
 int mainMenuIndex = 0;
 int mainMenuNextItem = 1;
 int mainMenuItemNum = 3;
 boolean menuUpdate = false;

 // initialize the library with the numbers of the interface pins
 LiquidCrystal lcd(13, 11, 10, 9, 8, 7);

 void setup() {
 // set up the LCD's number of rows and columns:
 lcd.begin(numRows, numCols);
 lcd.clear();
 lcd.setCursor(0, 0);
 lcd.print(">");
 lcd.setCursor(2, 0);
 lcd.print(mainMenu[mainMenuIndex]);
 lcd.setCursor(2, 1);
 lcd.print(mainMenu[mainMenuNextItem]);
 digitalWrite(lcdBackLightPin, HIGH);

 pinMode(lcdBackLightPin, OUTPUT);
 pinMode(upButtonPin, INPUT);
 pinMode(downButtonPin, INPUT);
 pinMode(setButtonPin, INPUT);
 pinMode(resetButtonPin, INPUT);

 }

 void loop() {
 if(digitalRead(upButtonPin))
 {
 mainMenuIndex++;
 if(mainMenuIndex >= mainMenuItemNum)
 {
 mainMenuIndex = 0;
 }  
 mainMenuNextItem++;
 if(mainMenuNextItem >= mainMenuItemNum)
 {
 mainMenuNextItem = 0;
 }
 menuUpdate = true;
 }
 else if(digitalRead(downButtonPin))
 {
 mainMenuIndex--;
 if(mainMenuIndex < 0)
 {
 mainMenuIndex = mainMenuItemNum - 1;
 }  
 mainMenuNextItem--;
 if(mainMenuNextItem < 0)
 {
 mainMenuNextItem = mainMenuItemNum - 1;
 }
 menuUpdate = true;
 }

 if(menuUpdate)
 {   
 lcd.clear();
 lcd.setCursor(0, 0);
 lcd.print(">");
 lcd.setCursor(2, 0);
 lcd.print(mainMenu[mainMenuIndex]);
 lcd.print(" <");
 lcd.setCursor(2, 1);
 lcd.print(mainMenu[mainMenuNextItem]);
 menuUpdate = false;
 delay(300);
 }

 }

You can download the file from here: xISTIxHSPC

Buttons assembled

As you can see, I put every button connector two a new column. This way it was easy to wire them and I needed to make cuts only between the connector pins. I also changed the code of the controller:

// include the library code:
 #include <LiquidCrystal.h>

 const int numRows = 2;
 const int numCols = 16;

 const int lcdBackLightPin = 12;
 const int upButtonPin = 6;
 const int downButtonPin = 5;
 const int setButtonPin = 4;
 const int resetButtonPin = 3;

 // initialize the library with the numbers of the interface pins
 LiquidCrystal lcd(13, 11, 10, 9, 8, 7);

 void setup() {
 // set up the LCD's number of rows and columns:
 lcd.begin(numRows, numCols);
 lcd.clear();
 lcd.setCursor(5, 1);
 lcd.print("XistiX");
 digitalWrite(lcdBackLightPin, HIGH);

 pinMode(lcdBackLightPin, OUTPUT);
 pinMode(upButtonPin, INPUT);
 pinMode(downButtonPin, INPUT);
 pinMode(setButtonPin, INPUT);
 pinMode(resetButtonPin, INPUT);
 }

 void loop() {
 if(digitalRead(upButtonPin))
 {
 lcd.setCursor(0, 0);
 lcd.print("UP Button");
 }
 else if(digitalRead(downButtonPin))
 {
 lcd.setCursor(0, 0);
 lcd.print("DOWN Button");
 }
 else if(digitalRead(setButtonPin))
 {
 lcd.setCursor(0, 0);
 lcd.print("SET Button");
 }
 else if(digitalRead(resetButtonPin)

)

 {

 lcd.setCursor(0, 0);

 lcd.print("RESET Button");

 }

 else

 {

 lcd.setCursor(0, 0);

 lcd.print("            ");

 }

 }

It prints to the screen which button is pressed. When you check the source you will notice that buttons actually has a priority order and you can’t press two more than one button at the same time. I used an if else if structure. I will change this later. It is simply so because it was the easiest to test the buttons and update the screen.

You can download the code as a file from here: xISTIx_Buttons

Push button circuit

I have put a two pin connector to a stripe and made a cut between the pins. then I connected one pin (the upper one in the picture) via a 10 kohm resistor to the ground. The same pin is also connected to pin 6 of the arduino.  The other pin is connected to 5v via a 500 ohm resistor. The push button shorts the two pins.

I have modified the LCD test program a bit. Now the LCD background light is on when the push button is pressed. It is just for testing purposes. Later I will change this.

Here is the code: HelloWorldLCDButton

LCD circuit ready

Hello World!

And here is the final design:

Final LCD circuit design

I also promised to upload the LCD test program:

// include the library code:
 #include <LiquidCrystal.h>

 const int numRows = 2;
 const int numCols = 16;

 const int lcdBackLightPin = 12;

 // initialize the library with the numbers of the interface pins
 LiquidCrystal lcd(13, 11, 10, 9, 8, 7);

 void setup() {
 // set up the LCD's number of rows and columns:
 lcd.begin(numRows, numCols);
 lcd.clear();
 lcd.setCursor(2, 0);
 lcd.print("Hello World!");

 pinMode(lcdBackLightPin, OUTPUT);
 }

 void loop() {
 digitalWrite(lcdBackLightPin, HIGH);
 lcd.setCursor(5, 1);
 lcd.print("xISTIx");
 delay(500);
 digitalWrite(lcdBackLightPin, LOW);
 lcd.setCursor(5, 1);
 lcd.print("XistiX");
 delay(500);
 }

Source file is here: xISTIx_Hello_LCD

My source file is based on this example: http://arduino.cc/en/Tutorial/LiquidCrystal

I just simplified the loop and changed the pin numbers according to my circuit. I also added the control for the LCD back light on pin 12.

Finally a comment for Linux 64 bit users. If you use the arduino package I have suggested earlier, you might face some compilation problem. It is because the LCD library is old in that package. I simply downloaded the arduino017 32 bit Linux software from the official arduino site and copied the LCD library from there. It works fine.

I took some pictures, but I do not have the possibility to upload them right now. They are on my phone and I do not have the USB cable with me. I know, I know it has bluetooth connection but after 5 minutes searching for the damn bluetooth activation on my WinXP office laptop I gave up. So pictures will come in the next post. I will also post the source code for the LCD test.

http://blog.makezine.com/archive/2009/07/arduino_on_64-bit_linux.html

Cooooool! It works fine with my Seeeduino which is basically an Arduino Diecimila. Unfortunately it does not support my Arduino Duemilanove boards. The ATmega328 chips are not supported by the avrdude config. If someone knows how to do that I would be glad to hear it.