Made a simple alphabets scrolling text using ideas and fonts from the following ppl below:-
Scrolling text ideas from hari ( http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1267391793/7 ) and A - Z bit patterns/fonts from aspro648 ( http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1203747843/22 )
Their setup was for common anode row whereas my LED Matrix is common cathode row.
I just swap the shiftOut lines and change the MSBFIRST to LSBFIRST to suit the common cathode
shiftOut(dataPin, clockPin, MSBFIRST, col); // column, scan 0 to 7 by shifting 1 bit at a time
shiftOut(dataPin, clockPin, LSBFIRST, ~buff); // Use LSB to swap the char, made for CA
Stanley
Full sktech :-
// Red 8x8 LED Matrix for common cathode row
//
// Youtube video : http://www.youtube.com/watch?v=UaMYlHw4rek
// Blog : http://arduino-for-beginners.blogspot.com/
//
//
// Turn rows to 0 to sink current, turn row to 1, nothing will happen
// Turn columns to 1 to source current per columns
//
// 8 x 220 ohm resistors connected to A-G pins on 75595 shift registers
// for common cathode rows
// Follow SPI pinout
int latchPin = 10; // LatchPin, 12 on 74595
int clockPin = 13; // clockPin, 11 on 74595
int dataPin = 11; // dataPin, 14 on 74595
int array1[]= { 1,2,4,8,16,32,64,128,255 };
int array2[]= { 1,3,7,15,31,63,127,255 };
// font by aspro648 ( http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1203747843/22 )
// First char is @, next is A, B, etc. Only lower case, no symbols.
// The @ will display as space character.
byte alphabets[][8] = {
{
0,0,0,0,0 }
,
{
31, 36, 68, 36, 31 }
,
{
127, 73, 73, 73, 54 }
,
{
62, 65, 65, 65, 34 }
,
{
127, 65, 65, 34, 28 }
,
{
127, 73, 73, 65, 65 }
,
{
127, 72, 72, 72, 64 }
,
{
62, 65, 65, 69, 38 }
,
{
127, 8, 8, 8, 127 }
,
{
0, 65, 127, 65, 0 }
,
{
2, 1, 1, 1, 126 }
,
{
127, 8, 20, 34, 65 }
,
{
127, 1, 1, 1, 1 }
,
{
127, 32, 16, 32, 127 }
,
{
127, 32, 16, 8, 127 }
,
{
62, 65, 65, 65, 62 }
,
{
127, 72, 72, 72, 48 }
,
{
62, 65, 69, 66, 61 }
,
{
127, 72, 76, 74, 49 }
,
{
50, 73, 73, 73, 38 }
,
{
64, 64, 127, 64, 64 }
,
{
126, 1, 1, 1, 126 }
,
{
124, 2, 1, 2, 124 }
,
{
126, 1, 6, 1, 126 }
,
{
99, 20, 8, 20, 99 }
,
{
96, 16, 15, 16, 96 }
,
{
67, 69, 73, 81, 97 }
,
};
void setup() {
Serial.begin(9600);
Serial.println("Ready...");
pinMode(latchPin, OUTPUT);
pinMode(clockPin, OUTPUT);
pinMode(dataPin, OUTPUT);
}
void clear_all() {
digitalWrite(latchPin, LOW);
shiftOut(dataPin, clockPin, MSBFIRST, 0 ); // Columns, 1 to turn ON
shiftOut(dataPin, clockPin, MSBFIRST, 0 ); // Rows, 0 to turn
digitalWrite(latchPin, HIGH);
}
void blink_all() {
for ( int i = 0; i < 8; i++) {
digitalWrite(latchPin, LOW);
shiftOut(dataPin, clockPin, LSBFIRST, B11111111); // Columns, 1 to turn ON
shiftOut(dataPin, clockPin, MSBFIRST, B00000000 ); // Rows, 0 to turn ON
digitalWrite(latchPin, HIGH);
delay(100);
clear_all();
delay(100);
}
}
void row_by_row() {
int row = 0;
for ( int i = 0; i < 8; i++) {
row = ~array1[i];
digitalWrite(latchPin, LOW);
shiftOut(dataPin, clockPin, LSBFIRST, B11111111); // Columns, 1 to turn ON
shiftOut(dataPin, clockPin, MSBFIRST, row); // Rows, 0 to turn ON
digitalWrite(latchPin, HIGH);
delay(100);
clear_all();
}
}
void col_by_col() {
int col = 0;
for ( int i = 0; i < 8; i++) {
col = array1[i];
digitalWrite(latchPin, LOW);
shiftOut(dataPin, clockPin, MSBFIRST, col); // Columns, 1 to turn ON
shiftOut(dataPin, clockPin, MSBFIRST, B0); // Rows, 0 to turn ON
digitalWrite(latchPin, HIGH);
delay(100);
clear_all();
}
}
void one_by_one() {
int row, col = 0;
// 2 loops of 8, 64 times
for (int i = 0; i < 8; i++) {
for (int j = 0; j < 8; j++ ) {
row = ~array1[i];
col = array1[j];
digitalWrite(latchPin, LOW);
shiftOut(dataPin, clockPin, MSBFIRST, col); // Columns, 1 to turn ON
shiftOut(dataPin, clockPin, MSBFIRST, row); // Rows, 0 to turn ON
digitalWrite(latchPin, HIGH);
delay(50);
clear_all();
}
}
}
void led_random() {
for ( int i = 0; i < 50; i++) {
digitalWrite(latchPin, LOW);
shiftOut(dataPin, clockPin, MSBFIRST, array1[random(8)]); // Columns, 1 to turn ON
shiftOut(dataPin, clockPin, MSBFIRST, ~array1[random(8)]); // Rows, 0 to turn ON
digitalWrite(latchPin, HIGH);
delay(100);
clear_all();
}
}
void char_loop() {
byte buff;
for (int x = 1; x < 27; x++) {
for (int y = 0; y < 4; y++) {
for (int j = 0; j < 10; j++) { // Display the char 10 times quickly
byte shift = B0000001;
if ( y > 0 ) { shift = shift << y; } // shift the column by y value
for (int i = 0; i < 8; i++) {
byte col = shift;
buff = alphabets[x][i];
digitalWrite(latchPin, LOW);
shiftOut(dataPin, clockPin, MSBFIRST, col); // column, scan 0 to 7 using shift by 1 bit
shiftOut(dataPin, clockPin, LSBFIRST, ~buff); // Use LSB to swap the char, made for CA
digitalWrite(latchPin, HIGH);
delay(5);
clear_all();
shift = shift << 1; // Move to the next column
} // i loop
} // j loop
delay(100);
} // y loop
} // x loop
}
void loop() {
//blink_all();
//delay(500);
//led_random();
//delay(500);
row_by_row();
delay(500);
col_by_col();
delay(500);
char_loop();
delay(1000);
led_random();
delay(500);
//one_by_one();
//delay(500);
} // end loop()
