From bb28428a445d4e840f19e945f47f6153defeca1e Mon Sep 17 00:00:00 2001
From: "rjbatista@gmail.com"
 <rjbatista@gmail.com@f0354187-03e1-8ba3-851e-26a5c8714c44>
Date: Thu, 15 Dec 2011 23:02:04 +0000
Subject: [PATCH] ISSUE #10: Support for starting position on
 setDisplayToString() methods

---
 CHANGES.txt |  3 +++
 TM1638.cpp  | 18 +++++++++++-------
 TM1638.h    |  6 ++++--
 3 files changed, 18 insertions(+), 9 deletions(-)

diff --git a/CHANGES.txt b/CHANGES.txt
index d3ed19a..7094d82 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -1,3 +1,6 @@
+- ISSUE #10: Support for starting position on setDisplayToString() methods.
+  WARNING: setDisplayToString methods have changed prototype and are incompatible with code compiled for 1.5.x (if you specified a custom font)
+
 Version 1.5.2
 
 - ISSUE #9: Backwards compatibility with previous Arduino IDE.
diff --git a/TM1638.cpp b/TM1638.cpp
index b4d76b3..df93151 100644
--- a/TM1638.cpp
+++ b/TM1638.cpp
@@ -124,22 +124,26 @@ void TM1638::clearDisplay()
   }
 }
 
-void TM1638::setDisplayToString(const char* string, const byte dots, const byte font[])
+void TM1638::setDisplayToString(const char* string, const byte dots, const byte pos, const byte font[])
 {
-  for (int i = 0; i < 8; i++) {
-    sendChar(i, font[string[i] - 32], dots & (1 << (7 - i)));
+  for (int i = 0; i < 8 - pos; i++) {
+  	if (string[i] != '\0') {
+	  sendChar(i + pos, font[string[i] - 32], dots & (1 << (7 - i)));
+	} else {
+	  break;
+	}
   }
 }
 
-void TM1638::setDisplayToString(const String string, const byte dots, const byte font[])
+void TM1638::setDisplayToString(const String string, const byte dots, const byte pos, const byte font[])
 {
   int stringLength = string.length();
 
-  for (int i = 0; i < 8; i++) {
+  for (int i = 0; i < 8 - pos; i++) {
     if (i < stringLength) {
-      sendChar(i, font[string.charAt(i) - 32], dots & (1 << (7 - i)));
+      sendChar(i + pos, font[string.charAt(i) - 32], dots & (1 << (7 - i)));
     } else {
-      sendChar(i, 0, dots & (1 << (7 - i)));
+      break;
     }
   }
 }
diff --git a/TM1638.h b/TM1638.h
index a3e5c5f..ed069a1 100644
--- a/TM1638.h
+++ b/TM1638.h
@@ -60,9 +60,11 @@ class TM1638
     /** Clear the display */
 	void clearDisplay();
     /** Set the display to the string (defaults to built in font) */
-	void setDisplayToString(const char* string, const byte dots = 0, const byte font[] = FONT_DEFAULT);
+	void setDisplayToString(const char* string, const byte dots = 0, const byte pos = 0,
+		const byte font[] = FONT_DEFAULT);
     /** Set the display to the String (defaults to built in font) */
-	void setDisplayToString(String string, const byte dots = 0, const byte font[] = FONT_DEFAULT);
+	void setDisplayToString(String string, const byte dots = 0, const byte pos = 0,
+		const byte font[] = FONT_DEFAULT);
 
     /** Set the LED at pos to color (TM1638_COLOR_RED, TM1638_COLOR_GREEN or both) */
     virtual void setLED(byte color, byte pos);