SparkCore OLED code

//*************************************//
// --- WIDE.HK---//
// - SSD131x PMOLED Controller -//
// - SCL, SDA, GND, VCC(3.3v 5v) --//
//*************************************//

/*
****************************************
This code is rewritten from the original code for the Arduino to control the I2C OLED from http://Wide.HK

The code below works to use the SparkCore microcontrller (available at http://spark.io )
Pins used on the SparkCore:

DO - SDA
D1 - SCL
3V
GND

see here for pins: http://docs.spark.io/#/hardware/pins-and-i-o-i2c

To call this method and update the display you can use cURL like this:

curl https://api.spark.io/v1/devices/{YOURDEVICEID}/update -d access_token={YOURACCESSTOKEN} -d "args=Hello World,Line 2 Text"

Make sure you replace the {YOURDEVICEID} and {YOURACCESSTOKEN} with information from your SparkCore
****************************************
*/

char OLED_Address = 0x3c;
char OLED_Command_Mode = 0x80;
char OLED_Data_Mode = 0x40;

void setup()
{
//begin Wire communication with OLED
Wire.begin();

//set the one external function to call to update the OLED with a message
Spark.function("update", update);

//initialize screen
SetupScreen();

sendCommand(0x01); // ** Clear display
sendMessage("started");

delay(1000);//wait one sec to see the started message

sendCommand(0x01); // ** Clear display
}

void loop()
{
//nothing happens in loop in this example
//just call 'update' from the web to update screen

}

int update(String args)
{
int status_code = 0;

sendCommand(0x01); // ** Clear display

args.replace("%20"," ");

int commaPosition = args.indexOf(",");//find if there is a delim character

if(commaPosition>-1){
//two lines
sendMessage(args.substring(0,commaPosition));//send first part
sendCommand(0xC0); // ** New Line
sendMessage(args.substring(commaPosition+1, args.length()));//send second part

status_code = 2;//lines

}else{
//one line
sendMessage(args);

status_code = 1;//lines
}

//how many lines sent to display
return status_code;
}

void SetupScreen(void){
// * I2C initial * //
delay(100);
sendCommand(0x2A); // ** Set "RE"=1 00101010B
sendCommand(0x71);
sendCommand(0x5C);
sendCommand(0x28);

sendCommand(0x08); // ** Set Sleep Mode On
sendCommand(0x2A); // ** Set "RE"=1 00101010B
sendCommand(0x79); // ** Set "SD"=1 01111001B

sendCommand(0xD5);
sendCommand(0x70);
sendCommand(0x78); // ** Set "SD"=0

sendCommand(0x08); // ** Set 5-dot, 3 or 4 line(0x09), 1 or 2 line(0x08)

sendCommand(0x06); // ** Set Com31->Com0 Seg0->Seg99

// ** Set OLED Characterization * //
sendCommand(0x2A); // ** Set "RE"=1
sendCommand(0x79); // ** Set "SD"=1

// ** CGROM/CGRAM Management * //
sendCommand(0x72); // ** Set ROM
sendCommand(0x00); // ** Set ROM A and 8 CGRAM

sendCommand(0xDA); // ** Set Seg Pins HW Config
sendCommand(0x10);

sendCommand(0x81); // ** Set Contrast
sendCommand(0xFF);

sendCommand(0xDB); // ** Set VCOM deselect level
sendCommand(0x30); // ** VCC x 0.83

sendCommand(0xDC); // ** Set gpio - turn EN for 15V generator on.
sendCommand(0x03);

sendCommand(0x78); // ** Exiting Set OLED Characterization
sendCommand(0x28);
sendCommand(0x2A);
//sendCommand(0x05); // ** Set Entry Mode
sendCommand(0x06); // ** Set Entry Mode
sendCommand(0x08);
sendCommand(0x28); // ** Set "IS"=0 , "RE" =0 //28
sendCommand(0x01);
sendCommand(0x80); // ** Set DDRAM Address to 0x80 (line 1 start)

delay(100);
sendCommand(0x0C); // ** Turn on Display

}

void sendData(unsigned char data)
{
Wire.beginTransmission(OLED_Address); // ** Start I2C
Wire.write(OLED_Data_Mode); // ** Set OLED Data mode
Wire.write(data);
Wire.endTransmission(); // ** End I2C
}

void sendCommand(unsigned char command)
{
Wire.beginTransmission(OLED_Address); // ** Start I2C
Wire.write(OLED_Command_Mode); // ** Set OLED Command mode
Wire.write(command);
Wire.endTransmission(); // ** End I2C
delay(10);
}