Button pad 4x4 hookup guide problem

Have questions about a SparkFun product or board? This is the place to be.

Moderators: phalanx, TS-Tim

Post Reply
Zozor26000
Posts: 1
Joined: Sat Feb 18, 2017 7:45 am

Button pad 4x4 hookup guide problem

Post by Zozor26000 » Sat Feb 18, 2017 9:46 am

Hello,
intro: I am a newbie in electronics, my project is to make a midi controller. I have done most of the parts.
I bought the button pad PCB 4x4 because it is cheaper than two 2x2 PCB. i have 2 Button pad rubber 2x2 (I only need 2 rows and 4 columns) to have 8 buttons.

my problem:
I followed this tutorial : https://learn.sparkfun.com/tutorials/bu ... hrome-leds .
I am blocked in the tutorial for the first exercice.
When I launch the code, nothing happen.

I use monochrome Led instead of RGB, I connect it like on the picture. (the only difference?)

I changed the code at line 5 and 6 to match my connections to my arduino uno.
"
static const uint8_t ledcolumnpins[NUM_LED_COLUMNS] = {8,9,10,11};
static const uint8_t colorpins[NUM_LED_ROWS] = {2,3,4,5};
"

Code: Select all

//config variables
#define NUM_LED_COLUMNS (4)
#define NUM_LED_ROWS (4)
#define NUM_COLORS (1)

// Global variables
static bool LED_buffer[NUM_LED_COLUMNS][NUM_LED_ROWS];
static int32_t next_advance;
static uint8_t led_index;

static const uint8_t ledcolumnpins[NUM_LED_COLUMNS]   = {8,9,10,11};
static const uint8_t colorpins[NUM_LED_ROWS] = {2,3,4,5};

static void setuppins()
{
  uint8_t i;

  // initialize all of the output pins

  // LED column lines
  for(i = 0; i < NUM_LED_COLUMNS; i++)
  {
    pinMode(ledcolumnpins[i], OUTPUT);

    // with nothing selected by default
    digitalWrite(ledcolumnpins[i], HIGH);
  }

  // LED row lines
  for(i = 0; i < NUM_LED_ROWS; i++)
  {
    pinMode(colorpins[i], OUTPUT);

    // with nothing driven by default
    digitalWrite(colorpins[i], LOW);
  }

}

static void scan()
{
  static uint8_t current = 0;
  uint8_t val;
  uint8_t i, j;

  // Select a column
  digitalWrite(ledcolumnpins[current], LOW);

  // write the row pins
  for(i = 0; i < NUM_LED_ROWS; i++)
  {
    if(LED_buffer[current][i])
    {
      digitalWrite(colorpins[i], HIGH);
    }
  }

  delay(1);

  digitalWrite(ledcolumnpins[current], HIGH);

  for(i = 0; i < NUM_LED_ROWS; i++)
  {
    digitalWrite(colorpins[i], LOW);
  }

  // Move on to the next column
  current++;
  if (current >= NUM_LED_COLUMNS)
  {
    current = 0;
  }

}

void setup() 
{
  // put your setup code here, to run once:
  Serial.begin(115200);
  Serial.print("Starting Setup...");

  // setup hardware
  setuppins();

  // init global variables
  next_advance = millis() + 1000;
  led_index = 0;

  // Initialize the LED display array
  for(uint8_t i = 0; i < NUM_LED_COLUMNS; i++)
  {
    for(uint8_t j = 0; j < NUM_LED_ROWS; j++)
    {
      LED_buffer[i][j] = false;
    }
  }
  // Set the first LED in the buffer on
  LED_buffer[0][0] = true;

  Serial.println("Setup Complete.");

}

void loop() 
{
  // put your main code here, to run repeatedly:

  scan();

  if(millis() >= next_advance)
  {
    next_advance = millis()+1000;

    LED_buffer[led_index/NUM_LED_COLUMNS][led_index%NUM_LED_COLUMNS] = false;
    led_index++;
    led_index %= (NUM_LED_COLUMNS * NUM_LED_ROWS);
    LED_buffer[led_index/NUM_LED_COLUMNS][led_index%NUM_LED_COLUMNS] = true;
  }
}
Thanks for your attention.
Could you help me please to make it works ?
Have you any idea of a more simple code just to test the LED ?

pictures:
Image
Image
Image
Image

ZipSnipe
Posts: 4
Joined: Fri Dec 22, 2017 3:13 am

Re: Button pad 4x4 hookup guide problem

Post by ZipSnipe » Mon Dec 25, 2017 8:25 pm

Wow nobody offered to help you out? umm I suspect your LED's I wondering if you have to use 4 wire leds

Post Reply