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Altera_Forum
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9 years ago

How to Initialize Char LCD using PIO (De0-Nano)

Hello to the whole forum, this is my very first thread so please be kind with me(= I'm trying to drive a char LCD using my de0 nano but no results yet.. My lcd is a 5v unit but since I nee...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
9 years ago

Everything solved, now I can print char and do stuff.

The second issue was caused by wrong timing.

The Clear Display command is quite slow and it take 1.52ms to be done, so I Changed usleep(2000).

As I said I've taken super wide delays since I wanted to avoid timing issue.

This is my working/corrected code, I hope it may help someone:

IOWR_ALTERA_AVALON_PIO_DIRECTION(PIO_LCD_DATA_BASE, 0b11111111);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_DATA_BASE, 0x00);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_COMMAND_BASE, 0b000);

usleep(16000);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_DATA_BASE, 0x38);

usleep(1);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_COMMAND_BASE, 0b001);

usleep(2);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_COMMAND_BASE, 0b000);

usleep(4500);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_DATA_BASE, 0x38);

usleep(1);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_COMMAND_BASE, 0b001);

usleep(2);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_COMMAND_BASE, 0b000);

usleep(200);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_DATA_BASE, 0x38);

usleep(1);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_COMMAND_BASE, 0b001);

usleep(2);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_COMMAND_BASE, 0b000);

usleep(200);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_DATA_BASE, 0x38);

usleep(1);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_COMMAND_BASE, 0b001);

usleep(2);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_COMMAND_BASE, 0b000);

usleep(200);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_DATA_BASE, 0x0E);

usleep(1);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_COMMAND_BASE, 0b001);

usleep(2);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_COMMAND_BASE, 0b000);

usleep(200);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_DATA_BASE, 0x01);

usleep(1);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_COMMAND_BASE, 0b001);

usleep(2);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_COMMAND_BASE, 0b000);

usleep(2000);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_DATA_BASE, 0x06);

usleep(1);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_COMMAND_BASE, 0b001);

usleep(2);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_COMMAND_BASE, 0b000);

usleep(200);

//data to test lcd

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_DATA_BASE, 0x41); // A

usleep(1);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_COMMAND_BASE, 0b101);

usleep(2);

IOWR_ALTERA_AVALON_PIO_DATA(PIO_LCD_COMMAND_BASE, 0b100);

usleep(2);