Added photoresistor and amb. light compensation

+ Added ambient light compensation logic
+ Added photocell on scheme
+ Added photoresitor to README.md

--HG--
branch : phtoresistor

.gitignore

@@ -1,6 +0,0 @@
-.vscode/*
-*.swp
-*.bak
-*.old
-*.orig
-*.clang-format

.hgignore

@@ -0,0 +1,6 @@
+^\.vscode
+\.swp$
+\.bak$
+\.old$
+\.orig$
+\.clang-format

.hgtags

@@ -0,0 +1,3 @@
+ee4999ebdd2d1b54512facafdd03c8a530ea4bfa v1.0
+1167bd4b622768ed17e116a4cbac3db90031e6f8 v1.1
+109112211e454e608911949914eaa2722fbfed7d v1.2

README.md

@@ -12,6 +12,8 @@
 * usb phone charger as power supply
 * 2 push buttons
 * 1 on/off switch
+* 1 photoresistor
+* 1 resistor to make secund shoulder of photosensitive "bridge", 10 kOhms, 0.25 watts
 * Gainta G521G enclosure (92x66.5x28мм)
 * 5m power cord
 
@@ -24,12 +26,3 @@
 ### Additional Notes:
 
 My RTC module is not very accurate due to bad quartz chrystal calibration, looks like it is not exactly 32768 Hz and clock runs faster than it should be, giving about 5-8 seconds runaway per day. So i have to implement time correction in software (temperature changes during day/month/year is not very big - about 10 degrees Celsius, so we can use software compensation without thermal compensation).
-
-This project split into 2 branches:
-
-* **default** that contains generic clock without any additional elements
-* **photoresistor** that contains additional hardware - photocell bridge - and software algorithm that compensates ambient light sensed by photocell basing on LED display charachteristics.
-
-### Stable tags for branches:
-v1.5 - default
-v1.4 - photoresistor

simpleclock.ino

@@ -6,6 +6,33 @@
  * 2 buttons for adjusting time.
  */
 
+/* This software distributed under BSD 2 Clause License
+ *
+ * Copyright (c) Sergei Fedosoff, All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * Redistributions of source code must retain the above copyright
+ * notice, this listof conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+ * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITYOF SUCH DAMAGE.
+ */
+
 /* DS1307 lib by FrankieChu for Seeed RTC module, in my case
  * Grove___RTC_DS1307-1.0.0.zip */
 #include <DS1307.h>
@@ -16,7 +43,7 @@ SevSeg Display;
 
 /* push button stuff */
 const long initial_delay = 600;   // wait a bit before spin numbers
-const long adjust_interval = 200; // delay between consecutive number increments
+const long adjust_interval = 200; // delay between consecutive number increnents
 const long bounce_delay = 20;     // contact bounce compensation
 const int hrs_btn = A0;           // put hour adjusting button on A0 lane
 const int min_btn = A1;           // put minute adjusting button on A1 lane
@@ -33,7 +60,11 @@ const long interval = 500;
 bool dot = true;
 
 /* time inaccuracy compensation flag */
-bool compflag = true;
+uint8_t compflag = 0;
+const uint8_t timeSkew = 6; // assume that clock runs faster than should
+
+/* ambient light compensation aka night mode */
+const int photoPin = A2;
 
 void setup()
 {
@@ -43,14 +74,19 @@ void setup()
 	byte digitPins[] = {9, 10, 11, 12};
 	byte segmentPins[] = {2, 3, 4, 5, 6, 7, 8, 13};
 	bool resistorsOnSegments = true; // 8 resistors, 330 Ohms each
-	bool updateWithDelays = false;   // Default. Recommended
+        /* updateWithDelays defaults to false and it is recommended value,
+	 * but i was unable to make my display to change brightness with
+	 * recommended value, so i have to use updateWithDelays=true,
+	 * in this case brightness gets changed.
+	 */
+	bool updateWithDelays = true;   // Default. Recommended
 
 	/* without it there is visual bug at 0 o'clock, and in current version
 	 * of SevSeg' setChars() does not dots at all */
 	bool leadingZeros = false;
 
 	Display.begin(hardwareConfig, numDigits, digitPins, segmentPins,
-	              resistorsOnSegments, updateWithDelays, leadingZeros);
+                      resistorsOnSegments, updateWithDelays, leadingZeros);
 	Display.setBrightness(100);
 
 	// setup clock
@@ -69,6 +105,9 @@ void setup()
 	// setup control buttons
 	pinMode(hrs_btn, INPUT_PULLUP);
 	pinMode(min_btn, INPUT_PULLUP);
+
+	// setup brigtness sensor
+	pinMode(photoPin, INPUT);
 }
 
 void loop()
@@ -77,12 +116,13 @@ void loop()
 	currentPushTimer = currentMillis;
 	char str[4];
 	float d;
+	unsigned int ambLight = analogRead(photoPin);
 
 	clock.getTime();
 
 	// push button magic
 	if ((!btn_pushed) and
-	    ((digitalRead(hrs_btn) == LOW) or (digitalRead(min_btn) == LOW))) {
+            ((digitalRead(hrs_btn) == LOW) or (digitalRead(min_btn) == LOW))) {
 		if (currentPushTimer - previousPushTimer >= initial_delay) {
 			previousPushTimer = currentPushTimer;
 			btn_pushed = true;
@@ -90,7 +130,7 @@ void loop()
 	}
 
 	if (btn_pushed and
-	    (digitalRead(hrs_btn) != LOW) and (digitalRead(min_btn) != LOW)) {
+            (digitalRead(hrs_btn) != LOW) and (digitalRead(min_btn) != LOW)) {
 		// compensate possible contact bounce with delay
 		if (currentPushTimer - previousPushTimer >= bounce_delay) {
 			btn_pushed = false;
@@ -134,15 +174,15 @@ void loop()
 	 */
 
 	if ((clock.hour == 21) and (clock.minute == 21) and
-	    (clock.second == 21) and (compflag)) {
+            (clock.second == 21) and (compflag == 0)) {
-		clock.fillByHMS(clock.hour, clock.minute, 14);
+		clock.fillByHMS(clock.hour, clock.minute, (clock.second - timeSkew));
 		clock.setTime();
-		compflag = false;
+		compflag = 1;
 	}
 
 	if ((clock.hour == 21) and (clock.minute == 21) and
-	    (clock.second == 23) and (!compflag)) {
+            (clock.second == 23) and (compflag == 1)) {
-		compflag = true;
+		compflag = 0;
 	}
 
 	// make blinking dot
@@ -164,6 +204,31 @@ void loop()
 		}
 	}
 
+	/* ambient light compensation
+	 * ambLight can be in range of 0..1023, if it 800, it has point to use fullbright
+	 */
+	if (ambLight >= 940) {
+		Display.setBrightness(100);
+	} else if ((ambLight < 900) and (ambLight >= 840)) {
+		Display.setBrightness(95);
+	} else if ((ambLight < 800) and (ambLight >= 735)) {
+		Display.setBrightness(70);
+	} else if ((ambLight < 700) and (ambLight >= 635)) {
+		Display.setBrightness(25);
+	} else if ((ambLight < 600) and (ambLight >= 530)) {
+		Display.setBrightness(15);
+	} else if ((ambLight < 500) and (ambLight >= 430)) {
+		Display.setBrightness(12);
+	} else if ((ambLight < 400) and (ambLight >= 325)) {
+		Display.setBrightness(10);
+	} else if ((ambLight < 300) and (ambLight >= 220)) {
+		Display.setBrightness(8);
+	} else if ((ambLight < 200) and (ambLight >= 110)) {
+		Display.setBrightness(7);
+	} else if (ambLight < 100) {
+		Display.setBrightness(6);
+	}
+
 	Display.refreshDisplay();
 }