Sketch is exactly the same as in the linked page:
int i;
int sign;
long value;
float result;
int clockpin = 4;
int datapin = 5;
unsigned long tempmicros;
void setup() {
Serial.begin(9600);
pinMode(clockpin, INPUT);
pinMode(datapin, INPUT);
}
void loop () {
while (digitalRead(clockpin)==HIGH) {} //if clock is LOW wait until it turns to HIGH
tempmicros=micros();
while (digitalRead(clockpin)==LOW) {} //wait for the end of the HIGH pulse
if ((micros()-tempmicros)>500) { //if the HIGH pulse was longer than 500 micros we are at the start of a new bit sequence
decode(); //decode the bit sequence
}
}
void decode() {
sign=1;
value=0;
for (i=0;i<23;i++) {
while (digitalRead(clockpin)==HIGH) { } //wait until clock returns to HIGH- the first bit is not needed
while (digitalRead(clockpin)==LOW) {} //wait until clock returns to LOW
if (digitalRead(datapin)==LOW) {
if (i<20) {
value|= 1<<i;
}
if (i==20) {
sign=-1;
}
}
}
result=(value*sign)/100.00;
Serial.println(result,2); //print result with 2 decimals
delay(1000);
}
Now that you mention it, it actually looks like the pulses are a but less than 5V. What if I supply the transistors with 6V?