Implement CalibratorState for ASCOM Conform

ASCOM_Driver/CoverCalibratorDriver.cs

@@ -86,6 +86,9 @@ public class CoverCalibrator : ICoverCalibratorV1
         private const string COMMAND_CALIBRATOR_OFF = "COMMAND:CALIBRATOR:OFF";
         private const string RESULT_CALIBRATOR_BRIGHTNESS = "RESULT:CALIBRATOR:BRIGHTNESS:";
 
+        private const string COMMAND_CALIBRATOR_GETSTATE = "COMMAND:CALIBRATOR:GETSTATE";
+        private const string RESULT_CALIBRATOR_STATE = "RESULT:CALIBRATOR:STATE:";
+
         private const int MAX_BRIGHTNESS = 255;
 
         /// <summary>
@@ -367,7 +370,46 @@ public CalibratorStatus CalibratorState
         {
             get
             {
-                return CalibratorStatus.Ready;
+                CheckConnected("CalibratorState");
+                tl.LogMessage("CalibratorState", "Sending request to device to read calibrator state");
+                objSerial.Transmit(COMMAND_CALIBRATOR_GETSTATE + SEPARATOR);
+                tl.LogMessage("CalibratorState", "Sent request to device to read calibrator state");
+                string response;
+                try
+                {
+                    response = objSerial.ReceiveTerminated(SEPARATOR).Trim();
+                }
+                catch (Exception e)
+                {
+                    tl.LogMessage("CalibratorState", "Exception: " + e.Message);
+                    throw e;
+                }
+                tl.LogMessage("CalibratorState", "Received response from device");
+                if (!response.StartsWith(RESULT_CALIBRATOR_STATE))
+                {
+                    tl.LogMessage("CalibratorState", "Invalid response from device: " + response);
+                    throw new ASCOM.DriverException("Invalid response from device: " + response);
+                }
+                string arg = response.Substring(RESULT_CALIBRATOR_STATE.Length);
+                int value;
+                try
+                {
+                    value = Int32.Parse(arg);
+                }
+                catch (FormatException)
+                {
+                    tl.LogMessage("CalibratorState", "Invalid state value received from device: " + arg);
+                    throw new ASCOM.DriverException("Invalid state value received from device: " + arg);
+                }
+                if (value < 0 || value > 5)
+                {
+                    tl.LogMessage("CalibratorState", "Invalid state value received from device: " + arg);
+                    throw new ASCOM.DriverException("Invalid state value received from device: " + arg);
+                }
+                else
+                {
+                    return (CalibratorStatus)value;
+                }
             }
         }
 

Arduino_Firmware/Arduino_Firmware.ino

@@ -4,31 +4,44 @@
  * Licensed under the MIT License. See the accompanying LICENSE file for terms.
  */
 
-constexpr auto DEVICE_GUID = "7e2006ab-88b5-4b09-b0b3-1ac3ca8da43e";
+constexpr auto DEVICE_GUID = "ff46156d-2bfe-4cf3-acca-68324f7d6d92";
 
-constexpr auto COMMAND_PING = "COMMAND:PING";
-constexpr auto RESULT_PING = "RESULT:PING:OK:";
+constexpr auto COMMAND_PING = "COMMAND::PING";
+constexpr auto RESULT_PING = "RESULT::PING::PONG:";
 
-constexpr auto COMMAND_INFO = "COMMAND:INFO";
-constexpr auto RESULT_INFO = "RESULT:INFO:DarkSkyGeek's Flat Panel Firmware v1.0";
+constexpr auto COMMAND_INFO = "COMMAND::INFO";
+constexpr auto RESULT_INFO = "RESULT::INFO::LHAFlatOne v1.0";
 
-constexpr auto COMMAND_CALIBRATOR_GETBRIGHTNESS = "COMMAND:CALIBRATOR:GETBRIGHTNESS";
-constexpr auto COMMAND_CALIBRATOR_ON = "COMMAND:CALIBRATOR:ON:";
-constexpr auto COMMAND_CALIBRATOR_OFF = "COMMAND:CALIBRATOR:OFF";
-constexpr auto RESULT_CALIBRATOR_BRIGHTNESS = "RESULT:CALIBRATOR:BRIGHTNESS:";
+constexpr auto COMMAND_CALIBRATOR_GETBRIGHTNESS = "COMMAND::CALIBRATOR::GETBRIGHTNESS";
+constexpr auto COMMAND_CALIBRATOR_ON = "COMMAND::CALIBRATOR::ON:";
+constexpr auto COMMAND_CALIBRATOR_OFF = "COMMAND::CALIBRATOR::OFF";
+constexpr auto COMMAND_CALIBRATOR_GETSTATE = "COMMAND::CALIBRATOR::GETSTATE";
+constexpr auto RESULT_CALIBRATOR_STATE = "RESULT::CALIBRATOR::STATE:";
+constexpr auto RESULT_CALIBRATOR_BRIGHTNESS = "RESULT::CALIBRATOR::BRIGHTNESS:";
 
-constexpr auto ERROR_INVALID_COMMAND = "ERROR:INVALID_COMMAND";
+constexpr auto ERROR_INVALID_COMMAND = "ERROR::INVALID_COMMAND";
 
 #define MIN_BRIGHTNESS 0
 #define MAX_BRIGHTNESS 255
-#define PWM_FREQ 20000
+#define PWM_FREQ 5000
+
+// initialize variables to precompute gamma correction table to ensure a perceived linearity to brightness
+constexpr float GAMMA = 2.2;
+int gammaTable[MAX_BRIGHTNESS + 1];
 
 byte brightness = 0;
+byte state = 1;
 
 int ledPin = 8;
 
 // The `setup` function runs once when you press reset or power the board.
 void setup() {
+    // Precompute gamma correction table
+    for (int i = 0; i < 256; i++) {
+        gammaTable[i] = map(pow((i - MIN_BRIGHTNESS) / float(MAX_BRIGHTNESS - MIN_BRIGHTNESS), GAMMA) * (MAX_BRIGHTNESS - MIN_BRIGHTNESS), 
+                            MIN_BRIGHTNESS, MAX_BRIGHTNESS, 0, 1023);
+    }
+
     // Initialize serial port I/O.
     Serial.begin(57600);
     while (!Serial) {
@@ -70,6 +83,9 @@ void loop() {
         else if (command == COMMAND_CALIBRATOR_OFF) {
             calibratorOff();
         }
+        else if (command == COMMAND_CALIBRATOR_GETSTATE) {
+            getState();
+        }
         else {
             handleInvalidCommand();
         }
@@ -92,18 +108,23 @@ void setBrightness() {
     // The nice thing about the `pwm` function is that we can set the frequency
     // to a much higher value (I use 20kHz) This does not work on all pins!
     // For example, it does not work on pin 7 of the Xiao, but it works on pin 8.
-    int value = map(brightness, MIN_BRIGHTNESS, MAX_BRIGHTNESS, 0, 1023);
+
+    // Do a lookup to the precomputed gamma table here
+    // int value = map(brightness, MIN_BRIGHTNESS, MAX_BRIGHTNESS, 0, 1023);
+    int value = gammaTable[brightness];
     pwm(ledPin, PWM_FREQ, value);
 }
 
 void calibratorOn(byte _brightness) {
     brightness = _brightness;
     setBrightness();
+    state = 3;
 }
 
 void calibratorOff() {
     brightness = 0;
     setBrightness();
+    state = 1;
 }
 
 //-- MISCELLANEOUS ------------------------------------------------------------
@@ -120,3 +141,8 @@ void sendFirmwareInfo() {
 void handleInvalidCommand() {
     Serial.println(ERROR_INVALID_COMMAND);
 }
+
+void getState() {
+    Serial.print(RESULT_CALIBRATOR_STATE);
+    Serial.println(state);
+}