File content as of revision 0:1a97e0243dbc:

#ifndef __ST7920_H
#define __ST7920_H

#define VERSION 1.0

#include <mbed.h>

// Instruction Set 1: (RE=0: Basic Instruction)
#define DISPLAY_CLEAR           0x01 // Fill DDRAM with "20H" and set DDRAM address counter (AC) to "00H"
#define RETURN_HOME             0x02 // Set DDRAM address counter (AC) to "00H", and put cursor
// to origin &#65533;Gthe content of DDRAM are not changed
#define ENTRY_MODE_SET          0x04 // Set cursor position and display shift when doing write or read
// operation
#define DISPLAY_CONTROL         0x08 // D=1: Display ON, C=1: Cursor ON, B=1: Character Blink ON
#define CURSOR_DISPLAY_CONTROL  0x10 // Cursor position and display shift control; the content of
// DDRAM are not changed
#define FUNCTION_SET            0x20 // DL=1 8-bit interface, DL=0 4-bit interface
// RE=1: extended instruction, RE=0: basic instruction
#define SET_CGRAM_ADDRESS       0x40 // Set CGRAM address to address counter (AC)
// Make sure that in extended instruction SR=0
#define SET_DDRAM_ADDRESS       0x80 // Set DDRAM address to address counter (AC)
// AC6 is fixed to 0

// Instruction set 2: (RE=1: extended instruction)
#define STANDBY                 0x01 // Enter standby mode, any other instruction can terminate.
// COM1&#65533;c32 are halted
#define SCROLL_OR_RAM_ADDR_SEL  0x02 // SR=1: enable vertical scroll position
// SR=0: enable CGRAM address (basic instruction)
#define REVERSE_BY_LINE         0x04 // Select 1 out of 4 line (in DDRAM) and decide whether to
// reverse the display by toggling this instruction
// R1,R0 initial value is 0,0
#define EXTENDED_FUNCTION_SET   0x20 // DL=1 :8-bit interface, DL=0 :4-bit interface
// RE=1: extended instruction, RE=0: basic instruction
#define SET_SCROLL_ADDRESS      0x40 // G=1 :graphic display ON, G=0 :graphic display OFF
#define SET_GRAPHIC_RAM_ADDRESS 0x80 // Set GDRAM address to address counter (AC)
// Set the vertical address first and followed the horizontal
// address by consecutive writings
// Vertical address range: AC5&#65533;cAC0, Horizontal address range: AC3&#65533;cAC0

// Parameters regarding Instruction Sets 1 & 2
#define DISPLAY_SHIFT_S         0x01 // Set 1, ENTRY_MODE_SET
#define INCREASE_DECREASE_ID    0x02 // Set 1, ENTRY_MODE_SET
#define CURSOR_BLINK_ON_B       0x01 // Set 1, DISPLAY_CONTROL
#define CURSOR_ON_C             0x02 // Set 1, DISPLAY_CONTROL
#define DISPLAY_ON_D            0x04 // Set 1, DISPLAY_CONTROL
#define SHIFT_RL                0x04 // Set 1, CURSOR_DISPLAY_CONTROL
#define CURSOR_SC               0x08 // Set 1, CURSOR_DISPLAY_CONTROL
#define EXTENDED_INSTRUCTION_RE 0x04 // Set 1, FUNCTION_SET; Set 2, EXTENDED_FUNTION_SET
#define DATA_LENGTH_DL          0x10 // Set 1, FUNCTION_SET; Set 2, EXTENDED_FUNTION_SET
#define REVERSE_BY_LINE_R0      0x01 // Set 2, REVERSE_BY_LINE
#define REVERSE_BY_LINE_R1      0x02 // Set 2, REVERSE_BY_LINE
#define EN_VERTICAL_SCROLL_SR   0x01 // Set 2, SCROLL_OR_RAM_ADDR_SEL
#define GRAPHIC_ON_G            0x02 // Set 2, EXTENDED_FUNTION_SET

#define BUSY_FLAG_BF            0x80

/*********************************************************************************/

class ST7920  {
public:
    /**
    *@brief Constructor, initializes the lcd on the respective pins.
    *@param control pins     RS,RW,E
    *@param databus        DB0-DB7    data pins
    *@return none
    *@  ----> pin PSB @ Vdd for 8/4-bit parallel bus mode.
    */
    ST7920 (PinName _RS, PinName _RW, PinName _E, PinName DB0, PinName DB1, PinName DB2, PinName DB3, PinName DB4, PinName DB5, PinName DB6, PinName DB7);


    /**
     *@brief Display initialision
     *
     *@param none
     *@return none
     *
     */
    void InitDisplay(void);


    /**
     *@brief Enable Extended Instructions, RE=1, Graphic on
     *
     *@param none
     *@return none
     *
     */
    void SetGraphicsMode(void);
    
        /**
     *@brief Go back to Basic Instructions, RE=0
     *
     *@param none
     *@return none
     *
     */
    void SetTextMode(void);

    /**
    *@brief Sets DDRAM address counter (AC) to '00H'
    *@basic function, clear screen
    *@param none
    *@return none
    *
    */
    void ClearScreen(void);
    
    void ReturnHome(void);
    void Standby(void);

    /**
    *@brief Places a string on the screen with internal characters from the HCGROM
    *@
    *@param row, column, string
    *@return none
    *
    */
/*
* DESCRIPTIONS:
* Place a string to the GLCD controller on the specified row and column.
* Due to the design of the ST7920 controller (to accomodate Mandarin and Cyrillic), you must place the text on the column
* according to the numbers above the diagram below:
*
* |--0--|--1--|--2--|...      ...|--7--|
* +--+--+--+--+--+---------------------+
* |H |e |l |l |o |  ...                | <- row 0 (address 0x80)
* +--+--+--+--+--+---------------------+
* |T |h |i |s |  |i ...                   | <- row 1 (address 0x90)
* +--+--+--+--+--+---------------------+
* |* |* |* |* |* |* ...                   | <- row 2 (address 0x88)
* +--+--+--+--+--+---------------------+
* |- |- |- |- |- |- ...                   | <- row 3 (address 0x98)
* +--+--+--+--+--+---------------------+ 
*
* Example:
* Writing "abc" onto the 1st column, and 1st row:
* |--0--|--1--|--2--|...      ...|--7--|
* +--+--+--+--+--+---------------------+
* |  |  |  |  |  |  ...                | <- row 0 (address 0x80)
* +--+--+--+--+--+---------------------+
* |  |  |a |b |c |  ...                   | <- row 1 (address 0x90)
* +--+--+--+--+--+---------------------+
* |  |  |  |  |  |  ...                   | <- row 2 (address 0x88)
* +--+--+--+--+--+---------------------+
* |  |  |  |  |  |  ...                   | <- row 3 (address 0x98)
* +--+--+--+--+--+---------------------+ 
*
******************************************************************************
*/
    void DisplayString(int Row,int Column, unsigned char *ptr,int length);

    /**
    *@brief Places a character on the screen with an internal character from the HCGROM
    *@
    *@param row, column, character
    *@return none
    *
    */    
/*
* DESCRIPTIONS:
* Place a character to the GLCD controller on the specified row and column.
* Due to the design of the ST7920 controller (to accomodate Mandarin and Cyrillic), you must place the text on the column
* according to the numbers above the diagram below:
* 
* |--0--|--1--|--2--|...      ...|--7--|
* +--+--+--+--+--+---------------------+
* |H |e |l |l |o |  ...                | <- row 0 (address 0x80)
* +--+--+--+--+--+---------------------+
* |T |h |i |s |  |i ...                   | <- row 1 (address 0x90)
* +--+--+--+--+--+---------------------+
* |* |* |* |* |* |* ...                   | <- row 2 (address 0x88)
* +--+--+--+--+--+---------------------+
* |- |- |- |- |- |- ...                   | <- row 3 (address 0x98)
* +--+--+--+--+--+---------------------+ 
*
* Example:
* Writing 'a' onto the 1st column, and 1st row:
* |--0--|--1--|--2--|...      ...|--7--|
* +--+--+--+--+--+---------------------+
* |  |  |  |  |  |  ...                | <- row 0 (address 0x80)
* +--+--+--+--+--+---------------------+
* |  |  |a |  |  |  ...                   | <- row 1 (address 0x90)
* +--+--+--+--+--+---------------------+
* |  |  |  |  |  |  ...                   | <- row 2 (address 0x88)
* +--+--+--+--+--+---------------------+
* |  |  |  |  |  |  ...                   | <- row 3 (address 0x98)
* +--+--+--+--+--+---------------------+ 
* 
*******************************************************************************
*/
    void DisplayChar(int Row, int Column,int inpChr);
    
     /**
    *@brief Fills the screen with the graphics described in a 1024-byte array
    *@
    *@param bitmap 128x64, bytes horizontal
    *@return none
    *
    */
    void FillGDRAM(unsigned char *bitmap);
    
    //same as FILLGDRAM, but turnes all the bytes from vertical to horizontal
    //now pictures for eg KS0108 can be used
    void FillGDRAM_Turned(unsigned char *bitmap);
    
    /**
    *@brief Clears the graphics RAM of the screen
    *@writes all pixels to zero
    *@param none
    *@return none
    *
    */
    void ClearGDRAM(void);
    

    
private:
    BusInOut DB;
    DigitalOut RS;
    DigitalOut RW;
    DigitalOut E;
    //DigitalOut RST;
    
    unsigned char screen[1024];
    
    unsigned int ByteReadLCD(void);

    void ByteWriteLCD(unsigned int data);

    /**
    *@brief Write instruction to the controller.
    *@param Command     command to send to the controller
    *@return none
    *
    */
    void  WriteInstruction(unsigned int Command);

    /**
     *@brief Write data byte to the controller.
     *@param data     data send to the controller chip (DDRAM/CGRAM/GDRAM)
     *@return none
     *
     */
    void WriteRAM(unsigned int data);

    /**
     *@brief Read busy flag, keep looking
     *@param none
     *@return none
     *
     */
    void ReadBusyFlag(void);

    /**
     *@brief Read Address Counter (AC) from the controller.
     *@param none
     *@return read Address Counter (AC) from the controller chip (DDRAM/CGRAM/GDRAM)
     *
     */
    unsigned int Read_AC(void);

    /**
     *@brief Read data byte from the controller.
     *@param none
     *@return data read from the controller chip (DDRAM/CGRAM/GDRAM)
     *
     */
    unsigned int ReadRAM(void);
};
#endif