lcd.c

/* LCD control for AKI-LAN
   2005/03/01
   This code was designed and coded by SHIBUYA K.
*/

#include "lcd.h"
#include "3052.h"

#define LCDPORT         PB.DR.BYTE
#define LCDPORTDDR      PB.DDR
#define WAITSTROBE() {asm("nop");asm("nop");asm("nop");asm("nop");}

typedef unsigned char uchar;

/*--------------------------------------------------------
    LCDpin   LED       H8pin
     DB4     LED0      PB0
     DB5     LED1      PB1
     DB6     LED2      PB2
     DB7     LED3      PB3
     RS                PB4
     E                 PB7
---------------------------------------------------------*/

static void microwait(int n)
{
  n *= 3;
  while(--n){
    WAITSTROBE();
  }
}

static void out(uchar data, int cmdflag)
{
  uchar udata,ldata,led;

  led = LCDPORT&0x0f;
  udata = (data>>4);
  ldata = (data&0x0f);
  if(!cmdflag){
    udata |= 0x10;
    ldata |= 0x10;
  }
  LCDPORT = udata;
  udata |= 0x80;
  LCDPORT = udata;
  WAITSTROBE();
  udata &= 0x7f;
  LCDPORT = udata;
  WAITSTROBE();

  LCDPORT=ldata;
  ldata |= 0x80;
  LCDPORT = ldata;
  WAITSTROBE();
  ldata &= 0x7f;
  LCDPORT = ldata;
  WAITSTROBE();
  LCDPORT = led;
  microwait(40);
}

void LCDInit()
{
  LCDPORTDDR = 0xff;
  microwait(15000); /* Wait more than 15ms after vcc rises to 4.5V */
  LCDPORT = 0x83;
  WAITSTROBE();
  LCDPORT = 0x03;
  microwait(4100);
  LCDPORT = 0x83;
  WAITSTROBE();
  LCDPORT = 0x03;
  microwait(4100);
  LCDPORT = 0x83;
  WAITSTROBE();
  LCDPORT = 0x03;
  microwait(40);
  LCDPORT = 0x82;
  WAITSTROBE();
  LCDPORT = 0x02;
  microwait(40);
  out(0x28,1); /* Function Set */
  out(0x08,1); /* Display OFF */
  out(0x01,1); /* Clear Display */
  microwait(1600);
  out(0x06,1); /* Entry Mode Set */
  out(0x0c,1); /* Display ON */
  LCDPORT = 0x0f;
}

void LCDClear()
{
  out(0x01,1);
  microwait(1600);
}

void LCDDisplay(const char *str, int line)
{
  unsigned char buf[16];
  unsigned int i;
  i = 0;
  while(*str && (i < sizeof(buf)))
    buf[i++] = (unsigned char)(*(str++));
  while(i < sizeof(buf))
    buf[i++] = ' ';
  if(line)
    out(0xc0,1);
  else
    out(0x80,1);
  out(0x06,1); /* Entry Mode Set */
  for(i = 0; i < sizeof(buf); i++)
    out(buf[i],0);
}