Added DHT22 sensor to the codebase and the setup. You have to download the DHTlib from http://playground.arduino.cc//Main/DHTLib on your own, and copy it to ~/sketchbook/libraries.

Pin8 is used. New commands: d? -> sensor state; dt? and dh? are for temperature and humidity.

Author: gajdipajti

README.md

@@ -5,6 +5,7 @@
  * The String->float conversion: http://forum.arduino.cc/index.php?topic=179666.msg1331654#msg1331654
  * LP Filter: http://sim.okawa-denshi.jp/en/PWMtool.php
  * PWM speedup from here: http://playground.arduino.cc/Code/PwmFrequency
+ * DHTlib, get it from here: http://playground.arduino.cc//Main/DHTLib
 
 # Start Here:
  1. Clone the repository to your sketchbook folder.
@@ -29,6 +30,11 @@
  * ilk? -> GET interlock state (always 0)
  * f? -> GET operation fault state (always 0)
  * leds? -> GET led status (1: Power on, 7: Laser on)
+ 
+# DHT22 Communication:
+ * d? -> GET sensor status (0: error, 1: ok)
+ * dt? -> GET temperature (float)
+ * dh? -> GET humidity (float)
 
 # Cobolt Laser Documentation
  * http://www.cobolt.se/wp-content/uploads/2014/10/Owners-Manual-05-01_140611.pdf

ldc205c/ldc205c.ino

@@ -0,0 +1,169 @@
+/*
+  A Controller for the Thorlabs LDC205C series equipment.
+  
+  Main Functions:
+    * ENABLE/DISABLE Laser -> Pin 13 + LED
+    * SET Laser Current    -> Pin 11 (Changed to 31 kHz)
+    * GET Laser Current    -> A0
+  LDC205C -> k=50mA/V
+  
+  Commands from Cobolt Gen5.
+  
+  Power fit: P=AI+b
+  B (y-intercept) = 2,158048764451327e+01 +/- 8,999878654085594e-02
+  A (slope) = 6,979088703376868e-01 +/- 1,292424325833072e-03
+*/
+
+// Please clone DHTlib from: https://github.com/RobTillaart/Arduino.git
+// Copy DHTlib to ~/sketchbook/libraries.
+#include <dht.h>
+dht DHT;
+
+unsigned long serialNumber = 302432729;
+float time;
+
+float A=0.69790887;
+float B=21.5804876;
+
+float kLDC500 = 50.0; // mA/V
+
+const int laserREM = 13;
+const int laserMod = 11;
+const int laserCTL = A0;
+const int dht22Pin =  8;
+
+String inputString = "";         // a string to hold incoming data
+boolean stringComplete = false;  // whether the string is complete
+
+void setup() {
+  pinMode(laserREM, OUTPUT);
+  pinMode(laserMod, OUTPUT);
+  // Change PWM Frequency for Timer2.  f=~31kHZ
+  // Copied the relevant part from here: http://playground.arduino.cc/Code/PwmFrequency
+  TCCR2B = TCCR2B & 0b11111000 | 0x01;
+  Serial.begin(115200);
+  // reserve 200 bytes for the inputString:
+  inputString.reserve(200);
+}
+
+void setCurrent(float i) {
+  // Lock to Max.
+  if (i > 100.00) { i = 110.00; }
+  int iDigit = i*1.535;
+  analogWrite(laserMod, iDigit);
+  Serial.println("OK\r");
+}
+
+float getVoltage() {
+  int ctlOut = analogRead(laserCTL);
+  // Convert the analog reading (which goes from 0 - 1023) to a voltage (0 - 5V):
+  return ctlOut*0.005; // voltage
+}
+
+float getCurrent() {
+  return getVoltage()*kLDC500;
+}
+
+float getPower() {
+  float p = (getCurrent()-B)/A;
+  if ( p > 0 ) return p;
+  else return 0.0;
+}
+
+float toFloat(String s) {
+  char carray[s.length() + 1];            //determine size of the array
+  s.toCharArray(carray, sizeof(carray));  //put readStringinto an array
+  float floatNumber = atof(carray);       //convert the array into a float
+  return floatNumber;
+}
+
+void loop() {
+  // get any incoming bytes:
+  if (stringComplete) {
+  // Status of 4 LEDs
+    if (inputString.startsWith("leds?")) {
+      // POWER ON + LASER ON + LASER LOCK + ERROR = 1 + 2 + 4 + 8
+      int leds = 1+digitalRead(laserREM)*6;
+      Serial.println(leds);
+  //  Laser ENABLE/DISABLE/STATE
+    } else if (inputString.startsWith("l")) {
+      if (inputString.substring(1,2) == "0") {
+        digitalWrite(laserREM,LOW);
+        Serial.println("OK\r");
+      } else if (inputString.substring(1,2) == "1") {
+        digitalWrite(laserREM,HIGH);
+        Serial.println("OK\r");
+      } else if (inputString.substring(1,2) == "?") {
+        Serial.println(digitalRead(laserREM));
+      }
+    //  Drive Current GET
+    } else if (inputString.startsWith("i?")) {
+      Serial.println(getCurrent());
+    //  Drive Current SET
+    } else if (inputString.startsWith("slc")) {
+      setCurrent(toFloat(inputString.substring(3)));
+    //  Power GET/SET
+    } else if (inputString.startsWith("p")) {
+      if ((inputString.substring(1,2) == "?") || (inputString.substring(1,3) == "a?")) {
+        Serial.println(getPower());
+      } else {
+        float fp = toFloat(inputString.substring(1));
+        float fpi;
+        if ( fp < 1.0 )  fpi = A*fp*1000.0+B;
+        else             fpi = A*fp+B;
+        if (fpi > 100.0) fpi = 100.0;
+        setCurrent(fpi);
+      }
+    // DHT22 Sensor TEMP/HUM
+    } else if (inputString.startsWith("d")) {
+      int chk = DHT.read22(dht22Pin);
+      if (inputString.substring(1,3) == "t?") {
+        Serial.println(DHT.temperature, 1);
+      } else if (inputString.substring(1,3) == "h?") {
+        Serial.println(DHT.humidity, 1);
+      } else if (inputString.substring(1,2) == "?")  {
+        if (chk == DHTLIB_OK) Serial.println("1");
+        else Serial.println("0");
+        }
+      }
+// Serial Number
+    } else if (inputString.startsWith("sn?")) {
+      Serial.println(serialNumber);
+// Working seconds
+    } else if (inputString.startsWith("hrs?")) {
+      time = millis()/60000.0;
+      Serial.println(time);
+// Interlock State, no real code behind
+    } else if (inputString.startsWith("ilk?")) {
+      Serial.println("0");
+// Operating fault GET, no real code behind
+    } else if (inputString.startsWith("f?")) {
+      Serial.println("0");
+    } else {
+      Serial.print("Syntax Error: ");
+      Serial.println(inputString);
+    }
+    // clear the string:
+    inputString = "";
+    stringComplete = false;
+  }
+}
+/*
+ SerialEvent occurs whenever a new data comes in the
+ hardware serial RX. This routine is run between each
+ time loop() runs, so using delay inside loop can delay
+ response. Multiple bytes of data may be available.
+ */
+void serialEvent() {
+  while (Serial.available()) {
+    // get the new byte:
+    char inChar = (char)Serial.read(); 
+    // add it to the inputString:
+    inputString += inChar;
+    // if the incoming character is a carriage return (ASCII 13),
+    // set a flag so the main loop can do something about it:
+    if (inChar == '\r') {
+      stringComplete = true;
+    } 
+  }
+}