LCD 4-bit

 /**
  ******************************************************************************
  * @file    Project/STM32F10x_StdPeriph_Template/main.c
  * @author  MCD Application Team
  * @version V3.5.0
  * @date    08-April-2011
  * @brief   Main program body
  ******************************************************************************
  * @attention
  *
  * THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS
  * WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE
  * TIME. AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY
  * DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING
  * FROM THE CONTENT OF SUCH FIRMWARE AND/OR THE USE MADE BY CUSTOMERS OF THE
  * CODING INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
  *
  * <h2><center>&copy; COPYRIGHT 2011 STMicroelectronics</center></h2>
  ******************************************************************************
  */

/* Includes ------------------------------------------------------------------*/
#include "stm32f10x.h"
#include <stdio.h>


/* Private typedef -----------------------------------------------------------*/
typedef struct{
  uint16_t pin; // assign something like GPIO_Pin_8
  GPIO_TypeDef * port; // assign someting like GPIOA
} MyPin;

MyPin DB0,DB1,DB2,DB3,DB4,DB5,DB6,DB7,DB[8],RS,RW,EN,LED;

/* Private define ------------------------------------------------------------*/
/*


*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
GPIO_InitTypeDef GPIO_InitStructure;

/* Private function prototypes -----------------------------------------------*/
#ifdef __GNUC__
/* With GCC/RAISONANCE, small printf (option LD Linker->Libraries->Small printf
   set to 'Yes') calls __io_putchar() */
#define PUTCHAR_PROTOTYPE int __io_putchar(int ch)
#else
#define PUTCHAR_PROTOTYPE int fputc(int ch, FILE *f)
#endif /* __GNUC__ */


/* Private functions ---------------------------------------------------------*/
void enable_gpio();
void writePin(MyPin pin, BitAction value);
BitAction readPin(MyPin pin);
/*----------------- LCD functions ------------*/
//Common LCD functions
void lcdCommon_sendByte(int byte,int howManyPins);
//8-bit mode LCD functions; you may delete ALL these 5 functions if you are using 4-bit
void lcd8_init();
void lcd8_sendCommand(int byte);
void lcd8_sendData(int byte);
void lcd8_print( char *s);
void lcd8_printx(char *s, int line, int column);
//4-bit mode LCD functions; you may delete ALL these 5 functions if you are using 8-bit
void lcd4_init();
void lcd4_sendCommand(int byte);
void lcd4_sendData(int byte);
void lcd4_print( char *s);
void lcd4_printx(char *s, int line, int column);

/**
  * @brief  Main program.
  * @param  None
  * @retval None
  */
void delay_ms(int ms){
  while(ms--)
    for(volatile uint16_t i = 0; i < 2300; i++);
}
void delay_us(volatile int ms){
  ms *= 4;
  while(ms--);
}

int main(void)
{
  enable_gpio();
  /* //8-bit example
  lcd8_init();
  lcd8_printx("8  Bit",0,8);
  lcd8_printx("LCD Driver",1,6);
  lcd8_printx("->",0,0);
  lcd8_printx("aemre",3,15);//
  /*/ // 4-bit example
  lcd4_init();
  lcd4_printx("4  Bit",0,8);
  lcd4_printx("LCD Driver",1,6);
  lcd4_printx("aemre",3,15);// */
  while(1);
}


/**
* bit0 = PA8#2
* bit1 = PA9#4
* bit2 = PC10#8
* bit3 = PB5#12
* bit4 = PB8#16
* bit5 = PC1#20
* bit6 = PC13#24
* bit7 = PB1#26
*
* RS = PB9#17
* RW = PC0#19
* EN = PB0#21
* LED = PC12#10
*/
void enable_gpio(){
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB |
                       RCC_APB2Periph_GPIOC, ENABLE);
  /* enable lcdCommon_sendByte() function pins */
  GPIO_InitTypeDef GPIO_InitStructureA, GPIO_InitStructureB,GPIO_InitStructureC;

  GPIO_InitStructureA.GPIO_Pin = GPIO_Pin_8 | GPIO_Pin_9;
  GPIO_InitStructureB.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_8 | GPIO_Pin_1 | GPIO_Pin_9 | GPIO_Pin_0;
  GPIO_InitStructureC.GPIO_Pin = GPIO_Pin_10 | GPIO_Pin_1 | GPIO_Pin_13 | GPIO_Pin_12 | GPIO_Pin_0;

  GPIO_InitStructureA.GPIO_Speed = GPIO_InitStructureB.GPIO_Speed = GPIO_InitStructureC.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructureA.GPIO_Mode = GPIO_InitStructureB.GPIO_Mode = GPIO_InitStructureC.GPIO_Mode = GPIO_Mode_Out_PP;

  GPIO_Init(GPIOA, &GPIO_InitStructureA);
  GPIO_Init(GPIOB, &GPIO_InitStructureB);
  GPIO_Init(GPIOC, &GPIO_InitStructureC);

  DB0.port = GPIOA; DB0.pin = GPIO_Pin_8;
  DB1.port = GPIOA; DB1.pin = GPIO_Pin_9;
  DB2.port = GPIOC; DB2.pin = GPIO_Pin_10;
  DB3.port = GPIOB; DB3.pin = GPIO_Pin_5;
  DB4.port = GPIOB; DB4.pin = GPIO_Pin_8;
  DB5.port = GPIOC; DB5.pin = GPIO_Pin_1;
  DB6.port = GPIOC; DB6.pin = GPIO_Pin_13;
  DB7.port = GPIOB; DB7.pin = GPIO_Pin_1;

  RS.port = GPIOB; RS.pin = GPIO_Pin_9;
  RW.port = GPIOC; RW.pin = GPIO_Pin_0;
  EN.port = GPIOB; EN.pin = GPIO_Pin_0;

  LED.port = GPIOC; LED.pin = GPIO_Pin_12;

  DB[0]=DB0;DB[1]=DB1;DB[2]=DB2;DB[3]=DB3;DB[4]=DB4;DB[5]=DB5;DB[6]=DB6;DB[7]=DB7;
}

void lcd8_init(){
  delay_ms(42);
  lcd8_sendCommand(0x3C);// 8-bit interface, 4 lines, 5x8
  delay_us(48);
  lcd8_sendCommand(0x3C);// 8-bit interface, 8 lines, 5x8  - again
  delay_us(48);
  lcd8_sendCommand(0x0C);// display ON, cursor off, blink off
  delay_us(48);
  lcd8_sendCommand(0x01);// clear display
  delay_ms(2);
  lcd8_sendCommand(0x06);// increment cursor, no shift
}

void lcd4_init(){
  delay_ms(42);
  /* only most significant 4 bytes sent, lcd4_sendCommand is not used*/
  writePin(RS,Bit_RESET);
  lcdCommon_sendByte(0x30,4);
  /* only most significant 4 bytes sent, lcd4_sendCommand is not used */

  delay_us(48);
  lcd4_sendCommand(0x2C);// 4-bit interface, 8 lines, 5x8  - again
  delay_us(48);
  lcd4_sendCommand(0x0C);// display ON, cursor off, blink off
  delay_us(48);
  lcd4_sendCommand(0x01);// clear display
  delay_ms(2);
  lcd4_sendCommand(0x06);// increment cursor, no shift
}
/**
* Convert boolean to BitAction
*/
BitAction conv(int b){
  return b ? Bit_SET : Bit_RESET;
}

void writePin(MyPin pin, BitAction value){
  GPIO_WriteBit(pin.port,pin.pin,value);
}

BitAction readPin(MyPin pin){
  return conv(GPIO_ReadInputDataBit(pin.port, pin.pin));
}

void lcdCommon_sendByte(int byte,int howManyPins){
  //First check if LCD is busy
  writePin(EN,Bit_SET);// To send data we need high to low signal
  for(int i = 0; i<howManyPins; i++)
    writePin(DB[7-i],conv(byte & (0x01 << (7-i))));//writePin(DB[7-i],conv(byte & (int) pow(2,7-i)));
  writePin(RW,Bit_RESET); // LCD is now in write mode
  delay_us(100); //wait sometime
  writePin(EN,Bit_RESET); // Now we send high to low signal
  delay_us(50); //it may need some time for the next operation
}

void lcd8_sendCommand(int byte){
  writePin(RS,Bit_RESET);
  lcdCommon_sendByte(byte,8);
}

void lcd4_sendCommand(int byte){
  writePin(RS,Bit_RESET);
  lcdCommon_sendByte(byte,4);
  lcdCommon_sendByte(byte<<4,4);
}

void lcd8_sendData(int byte){
  writePin(RS,Bit_SET);
  lcdCommon_sendByte(byte,8);
}

void lcd4_sendData(int byte){
  writePin(RS,Bit_SET);
  lcdCommon_sendByte(byte,4);
  lcdCommon_sendByte(byte<<4,4);
}

void lcd8_print( char *s){
  while( *s) lcd8_sendData( *s++);
}

void lcd4_print( char *s){
  while( *s) lcd4_sendData( *s++);
}

void lcd8_printx( char *s, int line, int column){
  int lineStarts[4] = {128, 192, 148, 212};
  lcd8_sendCommand(lineStarts[line%4]+column%20); //go to given position
  while( *s) lcd8_sendData( *s++);
}

void lcd4_printx( char *s, int line, int column){
  int lineStarts[4] = {128, 192, 148, 212};
  lcd4_sendCommand(lineStarts[line%4]+column%20); //go to given position
  while( *s) lcd4_sendData( *s++);
}

#ifdef  USE_FULL_ASSERT
void assert_failed(uint8_t* file, uint32_t line)
{
  while (1);
}
#endif

/**
  * @}
  */


/******************* (C) COPYRIGHT 2011 STMicroelectronics *****END OF FILE****/
/*

*/