Arduino - 74HC595 2
<source lang"C">
/* Using 2 7-segment displays with the 74HC595 shift registers CC by-sa-nc 3.0 http://tronixstuff.wordpress.com
*/
int latchpin = 8; // connect to pin 12 on the '595 int clockpin = 12; // connect to pin 11 on the '595 int datapin = 11; // connect to pin 14 on the '595 float b = 0; int c = 0; float d = 0; int e = 0; int speed = 300; // used to control speed of counting int segdisp[10] = {
3,159,37,13,153,73,65,27,1,9 };
void setup() {
pinMode(latchpin, OUTPUT); pinMode(clockpin, OUTPUT); pinMode(datapin, OUTPUT);
} void loop() {
// Count up for (int z=0; z<100; z++) { digitalWrite(latchpin, LOW); shiftOut(datapin, clockpin, LSBFIRST, 0); // clears the right display shiftOut(datapin, clockpin, LSBFIRST, 0); // clears the left display digitalWrite(latchpin, HIGH); if (z<10) { digitalWrite(latchpin, LOW); shiftOut(datapin, clockpin, LSBFIRST, segdisp[z]); // sends the digit down the serial path shiftOut(datapin, clockpin, LSBFIRST, 255); // sends a blank down the serial path to push the digit to the right digitalWrite(latchpin, HIGH); } else if (z>=10) { d=z%10; // find the remainder of dividing z by 10, this will be the right-hand digit c=int(d); // make it an integer, c is the right hand digit b=z/10; // divide z by 10 - the whole number value will be the left-hand digit e = int(b); // e is the left hand digit digitalWrite(latchpin, LOW); // send the digits down to the shift registers! shiftOut(datapin, clockpin, LSBFIRST, segdisp[c]); shiftOut(datapin, clockpin, LSBFIRST, segdisp[e]); digitalWrite(latchpin, HIGH); } delay(speed); } delay(2000); // Count down for (int z=99; z>=0; z--) { digitalWrite(latchpin, LOW); shiftOut(datapin, clockpin, LSBFIRST, 0); // clears the right display shiftOut(datapin, clockpin, LSBFIRST, 0); // clears the left display digitalWrite(latchpin, HIGH); if (z<10) { digitalWrite(latchpin, LOW); shiftOut(datapin, clockpin, LSBFIRST, segdisp[z]); // sends the digit down the serial path shiftOut(datapin, clockpin, LSBFIRST, 255); // sends a blank down the serial path to push the digit to the right digitalWrite(latchpin, HIGH); } else if (z>=10) { d=z%10; // find the remainder of dividing z by 10, this will be the right-hand digit c=int(d); // make it an integer, c is the right hand digit b=z/10; // divide z by 10 - the whole number value will be the left-hand digit e = int(b); // e is the left hand digit digitalWrite(latchpin, LOW); // send the digits down to the shift registers! shiftOut(datapin, clockpin, LSBFIRST, segdisp[c]); shiftOut(datapin, clockpin, LSBFIRST, segdisp[e]); digitalWrite(latchpin, HIGH); } delay(speed); } delay(2000);
}