Here is the schematic for the new barometer. The first op-amp and transistor is required to make a constant current source for the nph8100ah pressure transducer. The second op-amp is a differential amplifier which takes the difference in the output, and amplifies the voltage so at atmospheric pressure it puts out about 4 volts.
Lastly, here is the code for the new balloon exploder circuit.
/*
Balloon Exploder
Standby: Repeatedly blinks an LED at 1 second intervals
Recieves voltage at input, turns off standby
Waits x number of minutes, then sends a HIGH out to 12 and LED Rapid Blinks
*/
void setup() {
// initialize the digital pin as an output.
// Pin 13 has an LED connected
pinMode(13, OUTPUT); //pin 13 is set to an output
pinMode(8, INPUT); //pin 8 is set to an input
pinMode(12, OUTPUT); //pin 12 is set to output
digitalWrite(12,LOW); //pin 12 is initialized as low
}
void delayMinute()
// delays for a minute
{
int counter = 0;
while(counter<60){
delay(1000);
counter++;
}
}
void delayXMinutes(int x){ //delays for x amount of minutes
int counter = 0;
while(counter<x){
delayMinute();
counter++;
}
}
void loop(){
while(digitalRead(8)==LOW){ // while loop reads pin 8 and will stay in loop until pin 8 recieves 5 volts
digitalWrite(13, HIGH);
delay(1000);
digitalWrite(13, LOW); //slow blink to show that the switch has not been flipped yet
delay(1000);
}
delayXMinutes(5); // delays x number of minutes LIGHT IS OFF WHILE waiting
digitalWrite(12, HIGH); //sets pin 12 to 5 volts for transistor
while(digitalRead(8)==HIGH){ //stays in this state until switch is flipped again
digitalWrite(13, HIGH);
delay(100);
digitalWrite(13, LOW); //fast blink to show that the fuse has gone off
delay(100);
}
}