Revision 0:1a97e0243dbc, committed 2012-06-29

Comitter:

Bas

Date:

Fri Jun 29 22:47:51 2012 +0000

Commit message:

Function added for displaying vertical oriented bitmaps

Changed in this revision

diff -r 000000000000 -r 1a97e0243dbc st7920.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/st7920.cpp	Fri Jun 29 22:47:51 2012 +0000
@@ -0,0 +1,246 @@
+#include "st7920.h"
+
+ST7920::ST7920 (PinName _RS,PinName _RW, PinName _E, PinName DB0, PinName DB1, PinName DB2, PinName DB3, PinName DB4, PinName DB5, PinName DB6, PinName DB7)
+        : DB(DB0,DB1,DB2,DB3,DB4,DB5,DB6,DB7),RS(_RS), RW(_RW), E(_E) {
+
+    DB.output();
+    E.write(0);
+    RS.write(0);
+    RW.write(0);
+    InitDisplay();
+}
+
+unsigned int ST7920::ByteReadLCD() {
+    unsigned int data;
+
+    DB.input();
+    E.write(1);
+    data = DB.read();
+    E.write(0);
+    DB.output();
+
+    return data;
+}
+
+void ST7920::ByteWriteLCD(unsigned int data) {
+    DB.output();
+    E.write(1);
+    DB.write(data);
+    E.write(0);
+}
+
+void ST7920::WriteInstruction(unsigned int Command) {
+    ReadBusyFlag();
+    RS.write(0);
+    RW.write(0);
+    ByteWriteLCD(Command);
+}
+
+void ST7920::WriteRAM(unsigned int data) {
+    ReadBusyFlag();
+    RS.write(1);
+    RW.write(0);
+    ByteWriteLCD(data);
+}
+
+void ST7920::ReadBusyFlag() {
+    unsigned char data;
+
+    RS.write(0);
+    RW.write(1);
+    while ((data & 0x7F) == BUSY_FLAG_BF) {
+        data = ByteReadLCD();
+    }
+}
+
+unsigned int ST7920::Read_AC() {
+    RS.write(0);
+    RW.write(1);
+    return (ByteReadLCD() & 0x7F);
+}
+
+unsigned int ST7920::ReadRAM() {
+    ReadBusyFlag();
+    RS.write(1);
+    RW.write(1);
+    return ByteReadLCD();
+}
+
+void ST7920::InitDisplay() {
+    wait_ms(40); // wait 40ms
+    E.write(0);
+    WriteInstruction(FUNCTION_SET | DATA_LENGTH_DL); // 8 bits interface, RE=0
+    wait_us(100); // wait 100us
+    WriteInstruction(FUNCTION_SET | DATA_LENGTH_DL); // again
+    wait_us(37); // wait 37us
+    WriteInstruction(DISPLAY_CONTROL | DISPLAY_ON_D ); // display on
+    wait_us(100); // wait 100us
+    WriteInstruction(DISPLAY_CLEAR); // clear display
+    wait_ms(10); // wait 10ms
+    WriteInstruction(ENTRY_MODE_SET | INCREASE_DECREASE_ID); // move cursor right
+    wait_ms(10); // wait 10ms
+    WriteInstruction(RETURN_HOME);
+    SetGraphicsMode();
+}
+
+//************************************************************************************************
+//public methodes
+void ST7920::SetGraphicsMode() {
+    WriteInstruction(EXTENDED_FUNCTION_SET | DATA_LENGTH_DL);
+    WriteInstruction(EXTENDED_FUNCTION_SET | DATA_LENGTH_DL | EXTENDED_INSTRUCTION_RE); //RE=1 (Extended funtion set)
+    WriteInstruction(EXTENDED_FUNCTION_SET | DATA_LENGTH_DL | EXTENDED_INSTRUCTION_RE | GRAPHIC_ON_G);
+}
+
+void ST7920::SetTextMode() {
+    WriteInstruction(FUNCTION_SET | DATA_LENGTH_DL); // RE=0 (Basic funtion set)
+}
+
+void ST7920::ClearScreen() {
+    WriteInstruction(FUNCTION_SET | DATA_LENGTH_DL); // RE=0 (Basic funtion set)
+    WriteInstruction(DISPLAY_CLEAR);
+}
+
+void ST7920::ReturnHome() {
+    WriteInstruction(FUNCTION_SET | DATA_LENGTH_DL); //RE=0 (Basic funtion set)
+    WriteInstruction(RETURN_HOME);
+}
+
+void ST7920::Standby() {
+    WriteInstruction(EXTENDED_FUNCTION_SET | DATA_LENGTH_DL | EXTENDED_INSTRUCTION_RE); //RE=1 (Extended funtion set)
+    WriteInstruction(STANDBY);
+}
+
+//Basic text functions
+void ST7920::DisplayString(int Row,int Column,unsigned char *ptr,int length) {
+    int i=0;
+
+    switch (Row) {
+        case 0:
+            Column|=0x80;
+            break;
+        case 1:
+            Column|=0x90;
+            break;
+        case 2:
+            Column|=0x88;
+            break;
+        case 3:
+            Column|=0x98;
+            break;
+        default:
+            Column=0x80;
+            break;
+    }
+
+    if (Column%2!=0) {
+        Column-=1;
+        i=1;
+    }
+    WriteInstruction((unsigned int)Column);
+
+    if (i==1) {
+        WriteRAM(' ');
+    }
+    for (i=0; i<length; i++) {
+        WriteRAM((unsigned int)ptr[i]);
+    }
+}
+
+void ST7920::DisplayChar(int Row,int Column,int inpChr) {
+    int i=0;
+
+    switch (Row) {
+        case 0:
+            Column|=0x80; // SET_DDRAM_ADDRESS
+            break;
+        case 1:
+            Column|=0x90;
+            break;
+        case 2:
+            Column|=0x88;
+            break;
+        case 3:
+            Column|=0x98;
+            break;
+        default:
+            Column=0x80;
+            break;
+    }
+
+    if (Column%2!=0) {
+        Column-=1;
+        i=1;
+    }
+    WriteInstruction((unsigned int)Column);
+
+    if (i==1) {
+        WriteRAM(' ');
+    }
+    WriteRAM((unsigned int)inpChr);
+}
+
+// Graphic functions
+void ST7920::FillGDRAM(unsigned char *bitmap) {
+    unsigned char i, j, k ;
+
+    for ( i = 0 ; i < 2 ; i++ ) {
+        for ( j = 0 ; j < 32 ; j++ ) {
+            WriteInstruction(SET_GRAPHIC_RAM_ADDRESS | j) ;
+            if ( i == 0 ) {
+                WriteInstruction(SET_GRAPHIC_RAM_ADDRESS) ;
+            } else {
+                WriteInstruction(SET_GRAPHIC_RAM_ADDRESS | 0x08) ;
+            }
+            for ( k = 0 ; k < 16 ; k++ ) {
+                WriteRAM( *bitmap++ ) ;
+            }
+        }
+    }
+}
+
+void ST7920::FillGDRAM_Turned(unsigned char *bitmap) {
+    int i, j, k, m, offset_row, mask ;
+    unsigned char data;
+
+    for ( i = 0 ; i < 2 ; i++ ) { //upper and lower page
+        for ( j = 0 ; j < 32 ; j++ ) { //32 lines per page
+            WriteInstruction(SET_GRAPHIC_RAM_ADDRESS | j) ;
+            if ( i == 0 ) {
+                WriteInstruction(SET_GRAPHIC_RAM_ADDRESS) ;
+            } else {
+                WriteInstruction(SET_GRAPHIC_RAM_ADDRESS | 0x08) ;
+            }
+            mask=1<<(j%8); // extract bitnumber
+            //printf("mask: %d\r\n",mask);
+            for ( k = 0 ; k < 16 ; k++ ) { //16 bytes per line
+                offset_row=((i*32+j)/8)*128 + k*8; //y coordinate/8 = row 0-7 * 128 = byte offset, read 8 bytes
+                data=0;
+                for (m = 0 ; m < 8 ; m++) { // read 8 bytes from source
+
+                    if ((bitmap[offset_row+m] & mask)) { //pixel = 1
+                        data|=(128>>m);
+                    }
+                }
+                WriteRAM(data) ;
+            }
+        }
+    }
+}
+
+void ST7920::ClearGDRAM() {
+    unsigned char i, j, k ;
+
+    for ( i = 0 ; i < 2 ; i++ ) {
+        for ( j = 0 ; j < 32 ; j++ ) {
+            WriteInstruction(SET_GRAPHIC_RAM_ADDRESS | j) ;
+            if ( i == 0 ) {
+                WriteInstruction(SET_GRAPHIC_RAM_ADDRESS) ;
+            } else {
+                WriteInstruction(SET_GRAPHIC_RAM_ADDRESS | 0x08) ;
+            }
+            for ( k = 0 ; k < 16 ; k++ ) {
+                WriteRAM(0);
+            }
+        }
+    }
+}

diff -r 000000000000 -r 1a97e0243dbc st7920.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/st7920.h	Fri Jun 29 22:47:51 2012 +0000
@@ -0,0 +1,270 @@
+#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
\ No newline at end of file