Better scrolling-in and scrolling-out

Author: dplassgit

wordclock/wordclock.ino

@@ -5,13 +5,16 @@
 
 // Manual for library: http://lygte-info.dk/project/DisplayDriver%20UK.html
 
-#define numberOfDigits 16
+#define NUM_DIGITS 16
 const byte dataPin = A4;
 const byte clockPin = A5;
 
-LEDDisplayDriver display(dataPin, clockPin, true, numberOfDigits);
+LEDDisplayDriver display(dataPin, clockPin, true, NUM_DIGITS);
+
+#define BUFFER_SIZE 100
+char dateTimeString[BUFFER_SIZE];
+char temp[BUFFER_SIZE];
 
-char dateTimeString[32];
 
 ThreeWire myWire(9, 8, 10); // IO, SCLK, CE
 RtcDS1302<ThreeWire> Rtc(myWire);
@@ -27,7 +30,7 @@ void setup() {
   display.showTextScroll("Hello Wordclock");
   delay(2000);
 
-  Serial.println("hello serial Wordclock");
+  Serial.println("Hello serial Wordclock");
   Rtc.Begin();
   if (!Rtc.IsDateTimeValid()) {
     // Common Causes:
@@ -53,9 +56,9 @@ void setup() {
   populateTimeString(now);
   Serial.println(dateTimeString);
   if (now < compiled)  {
-    Serial.println("RTC is older than compile time!  (Updating DateTime)");
-    display.showTextScroll("RTC is older than compile time!  (Updating DateTime)");
+    Serial.println("RTC is older than compile time! (Updating DateTime)");
     Rtc.SetDateTime(compiled);
+    display.showTextScroll("RTC is older than compile time! (Updating DateTime)");
   } else if (now > compiled) {
     Serial.println("RTC is newer than compile time. (this is expected)");
   } else if (now == compiled)  {
@@ -76,9 +79,10 @@ void loop() {
     display.showTextScroll(dateTimeString);
     delay(2000);
     populateTimeString2(now);
-    display.showTextScroll(dateTimeString);
+    for (int i = 0; i < 5; ++i) {
+      display.showTextScroll(dateTimeString);
+    }
   }
-  delay(10000);
 }
 
 
@@ -114,21 +118,44 @@ void populateTimeString2(const RtcDateTime& dt) {
 
   if (minute >= 58 || minute <= 3) {
     if (hour == 0 || hour == 12 || hour == 24) {
-      // don't show "noon o'clock"
+      // don't show "noon o'clock" or "midnight o'clock"
       minuteStr = "";
       separator = "";
     } else {
-      // swap; instead of "O'clock Ten" it's "Ten O'clock".
+      // swap; instead of "O'clock Ten" show "Ten O'clock".
       const char *temp; temp = hourStr; hourStr = minuteStr; minuteStr = temp;
     }
   }
-  snprintf_P(dateTimeString,
-             countof(dateTimeString),
+  snprintf_P(temp,
+             countof(temp),
              PSTR("%s%s%s"),
              minuteStr,
              separator,
              hourStr
             );
+  // Figure out how many spaces to add to the beginning and end of the string;
+  // the string can be up to BUFFER_SIZE long, and have at most NUM_DIGITS spaces
+  // at the beginning and end.
+  int numSpace = 0;
+  int len = strlen(temp);
+  // I should math the shit out of this
+  while (len < BUFFER_SIZE && numSpace < NUM_DIGITS) {
+    numSpace++;
+    len+=2;
+  }
+  // Serial.print("oldlen: "); Serial.println(strlen(temp));
+  // Serial.print("newlen: "); Serial.println(len);
+  // Serial.print("numspace: "); Serial.println(numSpace);
+  // Clear the final destination; copy the temporary string into the right 
+  // spot, then fix the end-of-string marker.
+  memset(dateTimeString, ' ', BUFFER_SIZE);
+  strcpy(&dateTimeString[numSpace], temp);
+  dateTimeString[numSpace + strlen(temp)] = ' ';
+  dateTimeString[len] = 0;
+  Serial.print("old string: "); Serial.println(temp);
+  Serial.print("new string: ."); Serial.print(dateTimeString); Serial.println(".");
+  // .                Twenty to Four                .
+  // .                Quarter to Four                .
 }
 
 const char *getHour(int hour) {
@@ -152,16 +179,16 @@ const char *getHour(int hour) {
 const char *getMinute(int minute) {
   switch (minute) {
     case 58: case 59: case 0: case 1: case 2: case 3: return "O'clock";
-    case 4: case 5: case 6: case 7: return "Five Past";
+    case 4: case 5: case 6: case 7: return "Five minutes Past";
     case 8: case 9: case 10: case 11: case 12: case 13: return "Ten Past";
-    case 14: case 15: case 16: return "Quarter Past";
-    case 17: case 18: case 19: case 20: case 21: case 22: case 23: return "Twenty Past";
+    case 14: case 15: case 16: return "A Quarter Past";
+    case 17: case 18: case 19: case 20: case 21: case 22: case 23: return "Twenty minutes Past";
     case 24: case 25: case 26: case 27: return "Twenty five Past";
     case 28: case 29: case 30: case 31: case 32: return "Half Past";
     case 33: case 34: case 35: case 36: return "Twenty five to";
-    case 37: case 38: case 39: case 40: case 41: case 42: case 43: return "Twenty to";
-    case 44: case 45: case 46: return "Quarter to";
+    case 37: case 38: case 39: case 40: case 41: case 42: case 43: return "Twenty minutes to";
+    case 44: case 45: case 46: return "A Quarter to";
     case 47: case 48: case 49: case 50: case 51: case 52: return "Ten to";
-    case 53: case 54: case 55: case 56: case 57: return "Five to";
+    case 53: case 54: case 55: case 56: case 57: return "Five minutes to";
   }
 }