Updated Single Pulse Mode

Updated single pulse mode so that it has an ENABLED, ARMED, and FIRED state. The enabled pin toggles the single fire mode. The armed state toggles whether it's armed or not. The fire pin will only fire if it has been armed.

src/main.cpp

@@ -10,17 +10,30 @@
 * D23 - Amplitude Encoder Input
 * D24 - Period Encoder Input
 * D25 - Period Encoder Input
-* D26 - Waveform Select Encoder
-* D27 - Waveform Select Encoder
-* D28 - Single pulse flag (LOW enables single pulse mode)
+* D26 - Nothing
+* D27 - Single pulse armed pin. toggles the armed state when it recieves a falling signal
+* D28 - Single pulse enable pin (A FALLING signal toggles single pulse mode)
 * D29 - Single pulse trigger. (LOW will cause the arduino to send 1 waveform pulse)
 * D30 - Slow pulse flag (LOW enables a pulse rate of 3 pulses/second)
+* D31 - Armed state indicator light output
+* D32 - Fired state indicator light output
 */
 
 
+// Define pinouts
+#define waveform_pin DAC0
+#define amplitude_pin DAC1
+#define sync_pin 2
+#define single_pulse_arm_pin 27
+#define single_pulse_enable_pin 28
+#define single_pulse_trig_pin 29
+#define slow_pulse_flag_pin 30
+#define armed_indicator_pin 31
+#define fired_indicator_pin 32
+
+//Include necessary libraries
 #include <Arduino.h>
 #include <Encoder.h>
-#include <Wire.h>
 #include <LiquidCrystal_I2C.h>
 
 
@@ -34,13 +47,6 @@
 */
 #define sample_resolution 4
 
-#define waveform_pin DAC0
-#define amplitude_pin DAC1
-#define sync_pin 2
-#define single_pulse_flag_pin 28
-#define single_pulse_trig_pin 29
-#define slow_pulse_flag_pin 30
-
 // Number of waveforms available. Change this if you add or remove waveforms
 #define waveform_num 4
 // Array of waveform arrays. Currently holds four waveforms with 600 samples each.
@@ -62,9 +68,26 @@ long new_period = 4;
 long old_period = 4;
 
 
-//Used to debounce the trigger input
+//Setup values for arming and firing system
+volatile boolean is_enabled = false;
+volatile boolean is_armed = false;
 boolean has_single_pulsed = false;
-unsigned long deb_timer = 0;
+unsigned long debounce_timer = 0;
+
+// Toggles the armed state of single fire mode. (Only toggles is signle fire mdoe is already enabled.)
+void arm_single_fire(){
+  if(is_enabled){
+    is_armed = !is_armed;
+    // Toggle the armed indicator light
+    digitalWrite(armed_indicator_pin, !digitalRead(armed_indicator_pin));
+    digitalWrite(fired_indicator_pin, LOW);
+  }
+}
+
+// Toggles single fire mode
+void enable_single_fire(){
+  is_enabled = !is_enabled;
+}
 
 //Create LCD object
 LiquidCrystal_I2C lcd = LiquidCrystal_I2C(0x27, 16, 2);
@@ -105,15 +128,24 @@ void recalc_waveform(float percent_amplitude){
 }
 
 
-
 void setup() {
   //Immediately set the analog output to the mid point
   analogWrite(waveform_pin, 2048);
   //The sync pin can be run into an oscilliscope's trig channel to easiy find the waveform
   pinMode(sync_pin, OUTPUT);
-  pinMode(single_pulse_flag_pin, INPUT_PULLUP);
+  // Setup the rest of the IO pins
+  pinMode(single_pulse_enable_pin, INPUT_PULLUP);
+  pinMode(single_pulse_arm_pin, INPUT_PULLUP);
   pinMode(single_pulse_trig_pin, INPUT_PULLUP);
   pinMode(slow_pulse_flag_pin, INPUT_PULLUP);
+  pinMode(armed_indicator_pin, OUTPUT);
+  pinMode(fired_indicator_pin, OUTPUT);
+
+  //Set up interrupts to simplify single fire mode:
+  // This will call the arm_single_fire() function whenever it detects a falling signal on this pin
+  attachInterrupt(digitalPinToInterrupt(single_pulse_arm_pin), arm_single_fire, FALLING);
+  // Will call the enable_single_fire function whenever it detects a falling signal on this pin
+  attachInterrupt(digitalPinToInterrupt(single_pulse_enable_pin), enable_single_fire, FALLING);
 
   //Change the resolution of the analog ourput to its maximum (12 bit res)
   analogWriteResolution(12);
@@ -213,20 +245,26 @@ void loop() {
   // Creates a synch signal so an oscilliscope can more easily read irregular pulses
   digitalWrite(sync_pin, !digitalRead(sync_pin));
   
+
   // Check to see if the single pulse pin has been pulled LOW
-  if(!digitalRead(single_pulse_flag_pin)){
-    if(deb_timer-millis() > 100){
+  if(is_enabled){
+    if(is_armed && debounce_timer-millis() > 100){
       if(!digitalRead(single_pulse_trig_pin) && has_single_pulsed == false){
         generate_waveform(sample_resolution);
         has_single_pulsed = true;
-        deb_timer = millis();
+        debounce_timer = millis();
+        digitalWrite(fired_indicator_pin, HIGH);
+        digitalWrite(armed_indicator_pin, LOW);
+        is_armed = false;
       }
       else if(digitalRead(single_pulse_trig_pin)) {
         has_single_pulsed = false;
-        deb_timer = millis();
+        debounce_timer = millis();
       }
     }
-
+    if(debounce_timer-millis()>250){
+      digitalWrite(fired_indicator_pin, LOW);
+    }
   }
   else{
     generate_waveform(sample_resolution);