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Honored Contributorprinting to 16x2 LCD module
i got this code from here (http://forum.niosforum.com/forum/index.php?showtopic=229). this code initialize the lcd module.
#include <unistd.h># include <stdlib.h># include <stdio.h>
/* Commands which can be written to the COMMAND register */
enum /* Write to character RAM */
{
LCD_CMD_WRITE_DATA = 0x80
/* Bits 6:0 hold character RAM address */
};
enum /* Write to character generator RAM */
{
LCD_CMD_WRITE_CGR = 0x40
/* Bits 5:0 hold character generator RAM address */
};
enum /* Function Set command */
{
LCD_CMD_FUNCTION_SET = 0x20,
LCD_CMD_8BIT = 0x10,
LCD_CMD_TWO_LINE = 0x08,
LCD_CMD_BIGFONT = 0x04
};
enum /* Shift command */
{
LCD_CMD_SHIFT = 0x10,
LCD_CMD_SHIFT_DISPLAY = 0x08,
LCD_CMD_SHIFT_RIGHT = 0x04
};
enum /* On/Off command */
{
LCD_CMD_ONOFF = 0x08,
LCD_CMD_ENABLE_DISP = 0x04,
LCD_CMD_ENABLE_CURSOR = 0x02,
LCD_CMD_ENABLE_BLINK = 0x01
};
enum /* Entry Mode command */
{
LCD_CMD_MODES = 0x04,
LCD_CMD_MODE_INC = 0x02,
LCD_CMD_MODE_SHIFT = 0x01
};
enum /* Home command */
{
LCD_CMD_HOME = 0x02
};
enum /* Clear command */
{
LCD_CMD_CLEAR = 0x01
};
# define na_lcd_pio_command ((volatile int *) 0x80920850)# define na_lcd_pio_status ((volatile int *) 0x80920851)# define na_lcd_pio_wr_data ((volatile int *) 0x80920852)# define na_lcd_pio_rd_data ((volatile int *) 0x80920853)
# define PIO_LCD_IO_COMMAND (*na_lcd_pio_command)# define PIO_LCD_IO_STATUS (*na_lcd_pio_status)# define PIO_LCD_IO_WR_DATA (*na_lcd_pio_wr_data)# define PIO_LCD_IO_RD_DATA (*na_lcd_pio_rd_data)
void delay(int para)//delay for 0.2*para ms
{
int i=0,j=0;
for(i=0;i<para;i++)
for(j=0;j<10000;j++);
}
int main()
{
delay(75);
PIO_LCD_IO_COMMAND=LCD_CMD_FUNCTION_SET | LCD_CMD_8BIT;
delay(21);
PIO_LCD_IO_COMMAND=LCD_CMD_FUNCTION_SET | LCD_CMD_8BIT;
delay(10);
PIO_LCD_IO_COMMAND=LCD_CMD_FUNCTION_SET | LCD_CMD_8BIT;
delay(10);
PIO_LCD_IO_COMMAND=LCD_CMD_FUNCTION_SET | LCD_CMD_8BIT | LCD_CMD_TWO_LINE;
delay(10);
PIO_LCD_IO_COMMAND=LCD_CMD_ONOFF;
delay(10);
PIO_LCD_IO_COMMAND=LCD_CMD_CLEAR;
delay(10);
PIO_LCD_IO_COMMAND=LCD_CMD_MODES | LCD_CMD_MODE_INC;
delay(10);
PIO_LCD_IO_COMMAND=LCD_CMD_ONOFF | LCD_CMD_ENABLE_DISP;
delay(1000);
return 0;
}4 Replies
Altera_Forumi also tried to modified from pio_lcd16207.h. i merely add in the main function, change nr_delay to usleep. this time, nth happen to the lcd module.
Pls help! Thx!#include <unistd.h># include "pio_lcd16207.h"# include "nios2_system.h" /* Descriptions of standard peripherals */ static void delayShort(void); // Device constants // Internal LCD signals enum{ LCD_E = 0x400, LCD_RS = 0x200, LCD_RW = 0x100, LCD_DATA = 0x0FF }; // LCD Device Commands enum{ LCD_CMD_CLEAR = 0x01, LCD_CMD_HOME = 0x02, LCD_CMD_MODES = 0x04, LCD_CMD_ONOFF = 0x08, LCD_CMD_SHIFT = 0x10, LCD_CMD_FUNC = 0x20, LCD_CMD_RAMCGR= 0x40, LCD_CMD_RAMDDR= 0x80, LCD_CMD_FILLER= 0x00 }; // Device Parameters enum{ LCD_INTERFACE = 0x10, // interface width;1 (8 BITS)/0 (4BITS) LCD_NUMROWS = 0x08, //# of display rows; 1 (2 ROWS)/0 (1ROW) LCD_PIXEL = 0x04, // character pixel; 1(5x10 dots)/0 (5x7 dots) LCD_MOVE = 0x02, // character move direction; 1(increment)/0(decrement) LCD_SHIFT = 0x01, // move character with display shift; 1(shift)/0(no shift) LCD_DISP_SHIFT= 0x08 // action after character; 1(display shift)/0(character shift) }; enum{ LCD_COM_RESET = 0x30 }; // Some LCD parameters# define LCD_BUS_WIDTH 8# define LCD_PIXEL_WIDTH 5# define LCD_PIXEL_HEIGHT 8 // The hardcoded definition of where the LCD lives at // PIO port address np_pio *lcd = 0; void nr_pio_lcdcursorvisible(int bVisible) { if(bVisible) nr_pio_lcdwritecommand(0x0E); else nr_pio_lcdwritecommand(0x0C); } void nr_pio_lcdon(int bOn) { if(bOn) nr_pio_lcdwritecommand(0x0C); else nr_pio_lcdwritecommand(0x08); } void nr_pio_lcdclearscreen(void) { nr_pio_lcdwritecommand(LCD_CMD_CLEAR); } void nr_pio_lcdsetcursor(int row, int col) { unsigned char address; if(row > LCD_NUM_ROW) row = LCD_NUM_ROW; if(col > LCD_NUM_COL) col = LCD_NUM_COL; if(row == 0) address = 0; else if (row == 1) address = 0x40; else if (row == 2) address = 0x20; else address=0x60; address += col; nr_pio_lcdwritecommand(LCD_CMD_RAMDDR | address); } void nr_pio_lcdprintstringslowly(char *string, int time) { char tempBuffer; int i; i=0; sprintf(tempBuffer, string); // Show as much of the string as we can... while(tempBuffer) { nr_pio_lcdwritecharacter(tempBuffer); usleep(time); i++; } } /* * nr_pio_lcdwritescreen(char *string); * * This is probably the most useful routine. It * takes a string, and prints it to the LCD starting * from the first character. If the string is less * than 32 characters, fill the rest of the display * with blanks. If the string exceeds 32 characters, * truncate it. So sorry! */ void nr_pio_lcdwritescreen(char *string) { int row; int col; int done; int count; count=0; for(row=0; row < LCD_NUM_ROW; row++) { for(col=0; col < LCD_NUM_COL; col++) { nr_pio_lcdsetcursor(row,col); if(string == 0x00) // hit the end and stick there. nr_pio_lcdwritecharacter(0xA0); else nr_pio_lcdwritecharacter(string); } } } void nr_pio_lcdinit(np_pio *lcdPio) { static int beenInitialized; // uninitialized static variables get cleared each run! if(beenInitialized) return; if(!lcdPio) lcdPio = (np_pio *)na_lcd_16207_0; // pio in reference design... lcd = lcdPio; // Send first Reset usleep(15); nr_pio_lcdwritecommand(LCD_COM_RESET); // Send second Reset usleep(5); nr_pio_lcdwritecommand(LCD_COM_RESET); // Send third Reset usleep(1); nr_pio_lcdwritecommand(LCD_COM_RESET); // Setup interface parameters: 8 bit bus, 2 rows, 5x7 font usleep(1); nr_pio_lcdwritecommand(LCD_CMD_FUNC | LCD_INTERFACE | LCD_NUMROWS); // Turn Display Off usleep(1); nr_pio_lcdwritecommand(LCD_CMD_ONOFF); // Clear Display usleep(1); nr_pio_lcdwritecommand(LCD_CMD_CLEAR); // Setup Default Mode usleep(1); nr_pio_lcdwritecommand(LCD_CMD_MODES | LCD_MOVE); //ON usleep(1); nr_pio_lcdon(1); beenInitialized = 1; } void nr_pio_lcdwritecommand(unsigned char command) { // preserve the data on the lines, but clear the RS and RW line lcd->np_piodata=(lcd->np_piodata & ~(LCD_RS | LCD_RW | LCD_E)); // output the RS and RW lines.. but nothing else lcd->np_piodirection=(lcd->np_piodirection | (LCD_RS | LCD_RW | LCD_E)); delayShort(); // toggle the E line HIGH to latch the command lcd->np_piodata=(lcd->np_piodata | LCD_E); delayShort(); // output command word whilst E line is high lcd->np_piodata=(lcd->np_piodata & ~LCD_DATA); lcd->np_piodata=(lcd->np_piodata | command); lcd->np_piodirection=(lcd->np_piodirection | LCD_DATA); // toggle the E line LOW to latch the data lcd->np_piodata=(lcd->np_piodata & ~LCD_E); delayShort(); } void nr_pio_lcdwritecharacter(unsigned char character) { // preserve the data on the lines, but clear the RW and E line, set RS lcd->np_piodata=(lcd->np_piodata & ~(LCD_RW | LCD_E)); lcd->np_piodata=(lcd->np_piodata | LCD_RS); // output the RS and RW lines.. but nothing else lcd->np_piodirection=(lcd->np_piodirection | (LCD_RW | LCD_E | LCD_RS)); delayShort(); // toggle the E line HIGH to latch the command lcd->np_piodata=(lcd->np_piodata | LCD_E); delayShort(); // output command word whilst E line is high lcd->np_piodata=(lcd->np_piodata & ~LCD_DATA); lcd->np_piodata=(lcd->np_piodata | character); lcd->np_piodirection=(lcd->np_piodirection | LCD_DATA); // toggle the E line LOW to latch the data lcd->np_piodata=(lcd->np_piodata & ~LCD_E); } void delayShort(void) { int i; int v = 0; for(i=0;i<50;i++) v++; } int main(void) { lcd = (np_pio *)na_lcd_16207_0; // Send first Reset usleep(15); nr_pio_lcdwritecommand(LCD_COM_RESET); // Send second Reset usleep(5); nr_pio_lcdwritecommand(LCD_COM_RESET); // Send third Reset usleep(1); nr_pio_lcdwritecommand(LCD_COM_RESET); // Setup interface parameters: 8 bit bus, 2 rows, 5x7 font usleep(1); nr_pio_lcdwritecommand(LCD_CMD_FUNC | LCD_INTERFACE | LCD_NUMROWS); // Turn Display Off usleep(1); nr_pio_lcdwritecommand(LCD_CMD_ONOFF); // Clear Display usleep(1); nr_pio_lcdwritecommand(LCD_CMD_CLEAR); // Setup Default Mode usleep(1); nr_pio_lcdwritecommand(LCD_CMD_MODES | LCD_MOVE); //ON usleep(1); nr_pio_lcdon(1); printf("LCD initialized.\n"); usleep(1000); nr_pio_lcdwritecharacter('A'); printf("LCD written.\n"); usleep(5000); return 0; }- Altera_Forum
looks like i'm alone here... http://forum.niosforum.com/work2/style_emoticons/<#EMO_DIR#>/sad.gif
can anyone pls tell me how do i access the 3 pins? rw, rw, and e... direct assignment to na_lcd_16207_0->piodata doesnt work... - Altera_Forum--- Quote Start --- originally posted by jwlam@Aug 28 2006, 04:04 AM i got this code from here (http://forum.niosforum.com/forum/index.php?showtopic=229). this code initialize the lcd module.
#include <unistd.h># include <stdlib.h># include <stdio.h> /* commands which can be written to the command register */ enum /* write to character ram */ { lcd_cmd_write_data = 0x80 /* bits 6:0 hold character ram address */ }; enum /* write to character generator ram */ { lcd_cmd_write_cgr = 0x40 /* bits 5:0 hold character generator ram address */ }; enum /* function set command */ { lcd_cmd_function_set = 0x20, lcd_cmd_8bit = 0x10, lcd_cmd_two_line = 0x08, lcd_cmd_bigfont = 0x04 }; enum /* shift command */ { lcd_cmd_shift = 0x10, lcd_cmd_shift_display = 0x08, lcd_cmd_shift_right = 0x04 }; enum /* on/off command */ { lcd_cmd_onoff = 0x08, lcd_cmd_enable_disp = 0x04, lcd_cmd_enable_cursor = 0x02, lcd_cmd_enable_blink = 0x01 }; enum /* entry mode command */ { lcd_cmd_modes = 0x04, lcd_cmd_mode_inc = 0x02, lcd_cmd_mode_shift = 0x01 }; enum /* home command */ { lcd_cmd_home = 0x02 }; enum /* clear command */ { lcd_cmd_clear = 0x01 }; # define na_lcd_pio_command ((volatile int *) 0x80920850)# define na_lcd_pio_status ((volatile int *) 0x80920851)# define na_lcd_pio_wr_data ((volatile int *) 0x80920852)# define na_lcd_pio_rd_data ((volatile int *) 0x80920853) # define pio_lcd_io_command (*na_lcd_pio_command)# define pio_lcd_io_status (*na_lcd_pio_status)# define pio_lcd_io_wr_data (*na_lcd_pio_wr_data)# define pio_lcd_io_rd_data (*na_lcd_pio_rd_data) void delay(int para)//delay for 0.2*para ms { int i=0,j=0; for(i=0;i<para;i++) for(j=0;j<10000;j++); } int main() { delay(75); pio_lcd_io_command=lcd_cmd_function_set | lcd_cmd_8bit; delay(21); pio_lcd_io_command=lcd_cmd_function_set | lcd_cmd_8bit; delay(10); pio_lcd_io_command=lcd_cmd_function_set | lcd_cmd_8bit; delay(10); pio_lcd_io_command=lcd_cmd_function_set | lcd_cmd_8bit | lcd_cmd_two_line; delay(10); pio_lcd_io_command=lcd_cmd_onoff; delay(10); pio_lcd_io_command=lcd_cmd_clear; delay(10); pio_lcd_io_command=lcd_cmd_modes | lcd_cmd_mode_inc; delay(10); pio_lcd_io_command=lcd_cmd_onoff | lcd_cmd_enable_disp; delay(1000); return 0; }my question is: how to i print characters to the screen? i suppose i shud look for the address of the pins rs, r/w, and e. but i've yet to locate them.
at the mean time, i'm going thru pio_lcd16207.c and pio_lcd16207.h. i think i understand wat these codes r trying to do but i've yet to come out with a prog tat works.
pls advice. thx in advance.
<div align='right'><{post_snapback}> (index.php?act=findpost&pid=17891)</div> --- Quote End --- this is regester map address,pls see linux driver book,could anyone post the lcd driver?thanks
- Altera_Forum
jwlam,
have you got it working ? I am interested in this. Pls help me through. cheers
