Added I2C brightness control sketch.

Author: nseidle

firmware/Serial 7-Segment Display/Arduino_Examples/S7S_Example_I2CSettings/S7S_Example_I2CSettings.ino

@@ -0,0 +1,75 @@
+/*
+ 11-2-2012
+ Spark Fun Electronics
+ Nathan Seidle
+ 
+ This code is public domain but you buy me a beer if you use this and we meet someday (Beerware license).
+
+ Serial7Segment is an open source seven segment display. 
+
+ This is example code that shows how to control the brightness level of the display over I2C.
+ 
+ Note: This code expects the display to be listening at the default I2C address. If your display is not at 0x71, you can
+ do a software or hardware reset. See the Wiki for more info: 
+ http://github.com/sparkfun/Serial7SegmentDisplay/wiki/Special-Commands
+ 
+ To get this code to work, attached an Serial7Segment to an Arduino Uno using the following pins:
+ A5 to SCL
+ A4 to SDA
+ VIN to PWR
+ GND to GND
+
+*/
+
+#include <Wire.h>
+
+#define DISPLAY_ADDRESS1 0x71 //This is the default address of the OpenSegment with both solder jumpers open
+
+void setup() 
+{
+  Wire.begin(); //Join the bus as master
+
+  Serial.begin(9600); //Start serial communication at 9600 for debug statements
+  Serial.println("OpenSegment Example Code");
+
+  //Send the reset command to the display - this forces the cursor to return to the beginning of the display
+  Wire.beginTransmission(DISPLAY_ADDRESS1);
+  Wire.write('v');
+  Wire.endTransmission();
+}
+
+void loop() 
+{
+  Serial.println("Low brightness"); //Just a debug statement
+  Wire.beginTransmission(DISPLAY_ADDRESS1);
+  Wire.write(0x7A); // Brightness control command
+  Wire.write(0); // Set brightness level: 0% to 100%
+  Wire.endTransmission();
+  i2cSendString("b000"); //Send the four characters to the display
+  delay(2000); //Hang out for a bit before we go to the next brightness level
+
+  Serial.println("Mid brightness"); //Just a debug statement
+  Wire.beginTransmission(DISPLAY_ADDRESS1);
+  Wire.write(0x7A); // Brightness control command
+  Wire.write(50); // Set brightness level: 0% to 100%
+  Wire.endTransmission();
+  i2cSendString("b050"); //Send the four characters to the display
+  delay(2000); //Hang out for a bit before we go to the next brightness level
+
+  Serial.println("High brightness"); //Just a debug statement
+  Wire.beginTransmission(DISPLAY_ADDRESS1);
+  Wire.write(0x7A); // Brightness control command
+  Wire.write(100); // Set brightness level: 0% to 100%
+  Wire.endTransmission();
+  i2cSendString("b100"); //Send the four characters to the display
+  delay(2000); //Hang out for a bit before we go to the next brightness level
+}
+
+//Given a string, i2cSendString chops up the string and sends out the first four characters over i2c
+void i2cSendString(char *toSend)
+{
+  Wire.beginTransmission(DISPLAY_ADDRESS1); // transmit to device #1
+  for(byte x = 0 ; x < 4 ; x++)
+    Wire.write(toSend[x]); //Send a character from the array out over I2C
+  Wire.endTransmission(); //Stop I2C transmission
+}