samples: gpio: lcd: sample app for HD44780 LCD controller
Display text strings on parallel interfacing HD44780 based
generic LCD controller using GPIO pins to interface with
Arduino Due(SAM3). HD44780 is a popular controller and an
example can help using gpio pins in parallel with it. I
have tested it on JHD20x4 LCD panel for 4Bits & 8Bits
configuration. The code has been made generic so that user
can modify quite a few options.
Datasheets:
http://lcd-linux.sourceforge.net/pdfdocs/hd44780.pdf
Signed-off-by: Milind Deore <tomdeore@gmail.com>
Change-Id: If2809222466b462fa2f4c42b14a514828530f082
diff --git a/samples/drivers/lcd_hd44780/Makefile b/samples/drivers/lcd_hd44780/Makefile
new file mode 100644
index 0000000..7c40b87
--- /dev/null
+++ b/samples/drivers/lcd_hd44780/Makefile
@@ -0,0 +1,5 @@
+KERNEL_TYPE = nano
+BOARD = arduino_due
+CONF_FILE = prj.conf
+
+include ${ZEPHYR_BASE}/Makefile.inc
diff --git a/samples/drivers/lcd_hd44780/prj.conf b/samples/drivers/lcd_hd44780/prj.conf
new file mode 100644
index 0000000..a032cfb
--- /dev/null
+++ b/samples/drivers/lcd_hd44780/prj.conf
@@ -0,0 +1,3 @@
+CONFIG_GPIO=y
+CONFIG_NANO_TIMERS=y
+CONFIG_NANO_TIMEOUTS=y
diff --git a/samples/drivers/lcd_hd44780/src/Makefile b/samples/drivers/lcd_hd44780/src/Makefile
new file mode 100644
index 0000000..00066e1
--- /dev/null
+++ b/samples/drivers/lcd_hd44780/src/Makefile
@@ -0,0 +1 @@
+obj-y = main.o
diff --git a/samples/drivers/lcd_hd44780/src/main.c b/samples/drivers/lcd_hd44780/src/main.c
new file mode 100644
index 0000000..1175730
--- /dev/null
+++ b/samples/drivers/lcd_hd44780/src/main.c
@@ -0,0 +1,611 @@
+/*
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * @file Display text strings on HD44780 based 20x4 LCD controller
+ * using GPIO for parallel interface on Arduino Due.
+ *
+ * Datasheet: http://lcd-linux.sourceforge.net/pdfdocs/hd44780.pdf
+ *
+ * LCD Wiring
+ * ----------
+ *
+ * The wiring for the LCD is as follows:
+ * 1 : GND
+ * 2 : 5V
+ * 3 : Contrast (0-5V)*
+ * 4 : RS (Register Select)
+ * 5 : R/W (Read Write) - GROUND THIS PIN
+ * 6 : Enable or Strobe
+ * 7 : Data Bit 0 - NOT USED
+ * 8 : Data Bit 1 - NOT USED
+ * 9 : Data Bit 2 - NOT USED
+ * 10: Data Bit 3 - NOT USED
+ * 11: Data Bit 4
+ * 12: Data Bit 5
+ * 13: Data Bit 6
+ * 14: Data Bit 7
+ * 15: LCD Backlight +5V**
+ * 16: LCD Backlight GND
+ *
+ *
+ * Arduino Due
+ * -----------
+ *
+ * On Arduino Due:
+ * 1. IO_3 is PC28
+ * 2. IO_5 is PC25
+ * 3. IO_6 is PC24
+ * 4. IO_7 is PC23
+ * 5. IO_8 is PC22
+ * 6. IO_9 is PC21
+ *
+ * The gpio_atmel_sam3 driver is being used.
+ *
+ * This sample app display text strings per line & page wise.
+ *
+ * Every 3 second you should see this repeatedly
+ * on display:
+ * "
+ * *********************
+ * Arduino Due
+ * 20x4 LCD Display
+ * *********************
+ *
+ * ------------------
+ * - Zephyr Rocks!
+ * - My super RTOS
+ * ------------------
+ *
+ * --------HOME--------
+ * I am home!
+ *
+ * --------------------
+ */
+
+#include <zephyr.h>
+
+#include <misc/printk.h>
+#include <gpio.h>
+#include <sys_clock.h>
+#include <string.h>
+
+
+#if defined(CONFIG_GPIO_ATMEL_SAM3)
+#define GPIO_DRV_NAME CONFIG_GPIO_ATMEL_SAM3_PORTC_DEV_NAME
+#else
+#error "Unsupported GPIO driver"
+#endif
+
+#if defined(CONFIG_SOC_ATMEL_SAM3)
+/* Define GPIO OUT to LCD */
+#define GPIO_PIN_PC12_D0 12 /* PC12 - pin 51 */
+#define GPIO_PIN_PC13_D1 13 /* PC13 - pin 50 */
+#define GPIO_PIN_PC14_D2 14 /* PC14 - pin 49 */
+#define GPIO_PIN_PC15_D3 15 /* PC15 - pin 48 */
+#define GPIO_PIN_PC24_D4 24 /* PC24 - pin 6 */
+#define GPIO_PIN_PC23_D5 23 /* PC23 - pin 7 */
+#define GPIO_PIN_PC22_D6 22 /* PC22 - pin 8 */
+#define GPIO_PIN_PC21_D7 21 /* PC21 - pin 9 */
+#define GPIO_PIN_PC28_RS 28 /* PC28 - pin 3 */
+#define GPIO_PIN_PC25_E 25 /* PC25 - pin 5 */
+#define GPIO_NAME "GPIO_"
+#endif
+
+/* Commands */
+#define LCD_CLEAR_DISPLAY 0x01
+#define LCD_RETURN_HOME 0x02
+#define LCD_ENTRY_MODE_SET 0x04
+#define LCD_DISPLAY_CONTROL 0x08
+#define LCD_CURSOR_SHIFT 0x10
+#define LCD_FUNCTION_SET 0x20
+#define LCD_SET_CGRAM_ADDR 0x40
+#define LCD_SET_DDRAM_ADDR 0x80
+
+/* Display entry mode */
+#define LCD_ENTRY_RIGHT 0x00
+#define LCD_ENTRY_LEFT 0x02
+#define LCD_ENTRY_SHIFT_INCREMENT 0x01
+#define LCD_ENTRY_SHIFT_DECREMENT 0x00
+
+/* Display on/off control */
+#define LCD_DISPLAY_ON 0x04
+#define LCD_DISPLAY_OFF 0x00
+#define LCD_CURSOR_ON 0x02
+#define LCD_CURSOR_OFF 0x00
+#define LCD_BLINK_ON 0x01
+#define LCD_BLINK_OFF 0x00
+
+/* Display/cursor shift */
+#define LCD_DISPLAY_MOVE 0x08
+#define LCD_CURSOR_MOVE 0x00
+#define LCD_MOVE_RIGHT 0x04
+#define LCD_MOVE_LEFT 0x00
+
+/* Function set */
+#define LCD_8BIT_MODE 0x10
+#define LCD_4BIT_MODE 0x00
+#define LCD_2_LINE 0x08
+#define LCD_1_LINE 0x00
+#define LCD_5x10_DOTS 0x04
+#define LCD_5x8_DOTS 0x00
+
+/* Define some device constants */
+#define LCD_WIDTH 20 /* Max char per line */
+#define HIGH 1
+#define LOW 0
+#define ENABLE_DELAY 0.0100
+
+
+#define GPIO_PIN_WR(dev, pin, bit) \
+ do { \
+ if (gpio_pin_write((dev), (pin), (bit))) { \
+ printk("Err set " GPIO_NAME "%d! %x\n", (pin), (bit)); \
+ } \
+ } while (0) \
+
+
+#define GPIO_PIN_CFG(dev, pin, dir) \
+ do { \
+ if (gpio_pin_configure((dev), (pin), (dir))) { \
+ printk("Err cfg " GPIO_NAME "%d! %x\n", (pin), (dir)); \
+ } \
+ } while (0)
+
+
+struct pi_lcd_data {
+ uint8_t disp_func; /* Display Function */
+ uint8_t disp_cntl; /* Display Control */
+ uint8_t disp_mode; /* Display Mode */
+ uint8_t cfg_rows;
+ uint8_t row_offsets[4];
+};
+
+/* Default Configuration - User can update */
+struct pi_lcd_data lcd_data = {
+ .disp_func = LCD_4BIT_MODE | LCD_1_LINE | LCD_5x8_DOTS,
+ .disp_cntl = 0,
+ .disp_mode = 0,
+ .cfg_rows = 0,
+ .row_offsets = {0x00, 0x00, 0x00, 0x00}
+};
+
+void _set_row_offsets(int8_t row0, int8_t row1, int8_t row2, int8_t row3)
+{
+ lcd_data.row_offsets[0] = row0;
+ lcd_data.row_offsets[1] = row1;
+ lcd_data.row_offsets[2] = row2;
+ lcd_data.row_offsets[3] = row3;
+}
+
+
+void _pi_lcd_toggle_enable(struct device *gpio_dev)
+{
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC25_E, LOW);
+ task_sleep(SECONDS(ENABLE_DELAY));
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC25_E, HIGH);
+ task_sleep(SECONDS(ENABLE_DELAY));
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC25_E, LOW);
+ task_sleep(SECONDS(ENABLE_DELAY));
+}
+
+
+void _pi_lcd_4bits_wr(struct device *gpio_dev, uint8_t bits)
+{
+ /* High bits */
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC24_D4, LOW);
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC23_D5, LOW);
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC22_D6, LOW);
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC21_D7, LOW);
+ if ((bits & BIT(4)) == BIT(4)) {
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC24_D4, HIGH);
+ }
+ if ((bits & BIT(5)) == BIT(5)) {
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC23_D5, HIGH);
+ }
+ if ((bits & BIT(6)) == BIT(6)) {
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC22_D6, HIGH);
+ }
+ if ((bits & BIT(7)) == BIT(7)) {
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC21_D7, HIGH);
+ }
+
+ /* Toggle 'Enable' pin */
+ _pi_lcd_toggle_enable(gpio_dev);
+
+ /* Low bits */
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC24_D4, LOW);
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC23_D5, LOW);
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC22_D6, LOW);
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC21_D7, LOW);
+ if ((bits & BIT(0)) == BIT(0)) {
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC24_D4, HIGH);
+ }
+ if ((bits & BIT(1)) == BIT(1)) {
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC23_D5, HIGH);
+ }
+ if ((bits & BIT(2)) == BIT(2)) {
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC22_D6, HIGH);
+ }
+ if ((bits & BIT(3)) == BIT(3)) {
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC21_D7, HIGH);
+ }
+
+ /* Toggle 'Enable' pin */
+ _pi_lcd_toggle_enable(gpio_dev);
+}
+
+void _pi_lcd_8bits_wr(struct device *gpio_dev, uint8_t bits)
+{
+ /* High bits */
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC21_D7, LOW);
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC22_D6, LOW);
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC23_D5, LOW);
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC24_D4, LOW);
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC15_D3, LOW);
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC14_D2, LOW);
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC13_D1, LOW);
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC12_D0, LOW);
+
+ /* Low bits */
+ if ((bits & BIT(0)) == BIT(0)) {
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC12_D0, HIGH);
+ }
+ if ((bits & BIT(1)) == BIT(1)) {
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC13_D1, HIGH);
+ }
+ if ((bits & BIT(2)) == BIT(2)) {
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC14_D2, HIGH);
+ }
+ if ((bits & BIT(3)) == BIT(3)) {
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC15_D3, HIGH);
+ }
+ if ((bits & BIT(4)) == BIT(4)) {
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC24_D4, HIGH);
+ }
+ if ((bits & BIT(5)) == BIT(5)) {
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC23_D5, HIGH);
+ }
+ if ((bits & BIT(6)) == BIT(6)) {
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC22_D6, HIGH);
+ }
+ if ((bits & BIT(7)) == BIT(7)) {
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC21_D7, HIGH);
+ }
+
+ /* Toggle 'Enable' pin */
+ _pi_lcd_toggle_enable(gpio_dev);
+}
+
+void _pi_lcd_data(struct device *gpio_dev, uint8_t bits)
+{
+ if (lcd_data.disp_func & LCD_8BIT_MODE) {
+ _pi_lcd_8bits_wr(gpio_dev, bits);
+ } else {
+ _pi_lcd_4bits_wr(gpio_dev, bits);
+ }
+}
+
+void _pi_lcd_command(struct device *gpio_dev, uint8_t bits)
+{
+ /* mode = False for command */
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC28_RS, LOW);
+ _pi_lcd_data(gpio_dev, bits);
+}
+
+void _pi_lcd_write(struct device *gpio_dev, uint8_t bits)
+{
+ /* mode = True for character */
+ GPIO_PIN_WR(gpio_dev, GPIO_PIN_PC28_RS, HIGH);
+ _pi_lcd_data(gpio_dev, bits);
+}
+
+
+/*************************
+ * USER can use these APIs
+ *************************/
+/** Home */
+void pi_lcd_home(struct device *gpio_dev)
+{
+ _pi_lcd_command(gpio_dev, LCD_RETURN_HOME);
+ task_sleep(USEC(2000)); /* wait for 4.1ms */
+}
+
+/** Set curson position */
+void pi_lcd_set_cursor(struct device *gpio_dev, uint8_t col, uint8_t row)
+{
+ size_t max_lines;
+
+ max_lines = (sizeof(lcd_data.row_offsets) / sizeof(*lcd_data.row_offsets));
+ if (row >= max_lines) {
+ row = max_lines - 1; /* Count rows starting w/0 */
+ }
+ if (row >= lcd_data.cfg_rows) {
+ row = lcd_data.cfg_rows - 1; /* Count rows starting w/0 */
+ }
+ _pi_lcd_command(gpio_dev, (LCD_SET_DDRAM_ADDR | (col + lcd_data.row_offsets[row])));
+}
+
+
+/** Clear display */
+void pi_lcd_clear(struct device *gpio_dev)
+{
+ _pi_lcd_command(gpio_dev, LCD_CLEAR_DISPLAY);
+ task_sleep(USEC(2000)); /* wait for 4.1ms */
+}
+
+
+/** Display ON */
+void pi_lcd_display_on(struct device *gpio_dev)
+{
+ lcd_data.disp_cntl |= LCD_DISPLAY_ON;
+ _pi_lcd_command(gpio_dev,
+ LCD_DISPLAY_CONTROL | lcd_data.disp_cntl);
+}
+
+/** Display OFF */
+void pi_lcd_display_off(struct device *gpio_dev)
+{
+ lcd_data.disp_cntl &= ~LCD_DISPLAY_ON;
+ _pi_lcd_command(gpio_dev,
+ LCD_DISPLAY_CONTROL | lcd_data.disp_cntl);
+}
+
+
+/** Turns cursor off */
+void pi_lcd_cursor_off(struct device *gpio_dev)
+{
+ lcd_data.disp_cntl &= ~LCD_CURSOR_ON;
+ _pi_lcd_command(gpio_dev,
+ LCD_DISPLAY_CONTROL | lcd_data.disp_cntl);
+}
+
+/** Turn cursor on */
+void pi_lcd_cursor_on(struct device *gpio_dev)
+{
+ lcd_data.disp_cntl |= LCD_CURSOR_ON;
+ _pi_lcd_command(gpio_dev,
+ LCD_DISPLAY_CONTROL | lcd_data.disp_cntl);
+}
+
+
+/** Turn off the blinking cursor */
+void pi_lcd_blink_off(struct device *gpio_dev)
+{
+ lcd_data.disp_cntl &= ~LCD_BLINK_ON;
+ _pi_lcd_command(gpio_dev,
+ LCD_DISPLAY_CONTROL | lcd_data.disp_cntl);
+}
+
+/** Turn on the blinking cursor */
+void pi_lcd_blink_on(struct device *gpio_dev)
+{
+ lcd_data.disp_cntl |= LCD_BLINK_ON;
+ _pi_lcd_command(gpio_dev,
+ LCD_DISPLAY_CONTROL | lcd_data.disp_cntl);
+}
+
+/** Scroll the display left without changing the RAM */
+void pi_lcd_scroll_left(struct device *gpio_dev)
+{
+ _pi_lcd_command(gpio_dev, LCD_CURSOR_SHIFT |
+ LCD_DISPLAY_MOVE | LCD_MOVE_LEFT);
+}
+
+/** Scroll the display right without changing the RAM */
+void pi_lcd_scroll_right(struct device *gpio_dev)
+{
+ _pi_lcd_command(gpio_dev, LCD_CURSOR_SHIFT |
+ LCD_DISPLAY_MOVE | LCD_MOVE_RIGHT);
+}
+
+/** Text that flows from left to right */
+void pi_lcd_left_to_right(struct device *gpio_dev)
+{
+ lcd_data.disp_mode |= LCD_ENTRY_LEFT;
+ _pi_lcd_command(gpio_dev,
+ LCD_ENTRY_MODE_SET | lcd_data.disp_cntl);
+}
+
+/** Text that flows from right to left */
+void pi_lcd_right_to_left(struct device *gpio_dev)
+{
+ lcd_data.disp_mode &= ~LCD_ENTRY_LEFT;
+ _pi_lcd_command(gpio_dev,
+ LCD_ENTRY_MODE_SET | lcd_data.disp_cntl);
+}
+
+/** Right justify text from the cursor location */
+void pi_lcd_auto_scroll_right(struct device *gpio_dev)
+{
+ lcd_data.disp_mode |= LCD_ENTRY_SHIFT_INCREMENT;
+ _pi_lcd_command(gpio_dev,
+ LCD_ENTRY_MODE_SET | lcd_data.disp_cntl);
+}
+
+/** Left justify text from the cursor location */
+void pi_lcd_auto_scroll_left(struct device *gpio_dev)
+{
+ lcd_data.disp_mode &= ~LCD_ENTRY_SHIFT_INCREMENT;
+ _pi_lcd_command(gpio_dev,
+ LCD_ENTRY_MODE_SET | lcd_data.disp_cntl);
+}
+
+void pi_lcd_string(struct device *gpio_dev, char *msg)
+{
+ int i;
+ int len = 0;
+ uint8_t data;
+
+ len = strlen(msg);
+ if (len > LCD_WIDTH) {
+ printk("Too long message! len %d %s\n", len, msg);
+ }
+
+ for (i = 0; i < len; i++) {
+ data = msg[i];
+ _pi_lcd_write(gpio_dev, data);
+ }
+}
+
+
+/** LCD initialization function */
+void pi_lcd_init(struct device *gpio_dev, uint8_t cols, uint8_t rows, uint8_t dotsize)
+{
+ if (rows > 1) {
+ lcd_data.disp_func |= LCD_2_LINE;
+ }
+ lcd_data.cfg_rows = rows;
+
+ _set_row_offsets(0x00, 0x40, 0x00 + cols, 0x40 + cols);
+
+ /* For 1 line displays, a 10 pixel high font looks OK */
+ if ((dotsize != LCD_5x8_DOTS) && (rows == 1)) {
+ lcd_data.disp_func |= LCD_5x10_DOTS;
+ }
+
+ /* SEE PAGE 45/46 FOR INITIALIZATION SPECIFICATION!
+ * according to datasheet, we need at least 40ms after power rises
+ * above 2.7V before sending commands. Arduino can turn on way
+ * before 4.5V so we'll wait 50
+ */
+ task_sleep(USEC(50000));
+
+ /* this is according to the hitachi HD44780 datasheet
+ * figure 23/24, pg 45/46 try to set 4/8 bits mode
+ */
+ if (lcd_data.disp_func & LCD_8BIT_MODE) {
+ /* 1st try */
+ _pi_lcd_command(gpio_dev, 0x30);
+ task_sleep(USEC(4500)); /* wait for 4.1ms */
+
+ /* 2nd try */
+ _pi_lcd_command(gpio_dev, 0x30);
+ task_sleep(USEC(4500)); /* wait for 4.1ms */
+
+ /* 3rd try */
+ _pi_lcd_command(gpio_dev, 0x30);
+ task_sleep(USEC(150)); /* wait for 100us */
+
+ /* Set 4bit interface */
+ _pi_lcd_command(gpio_dev, 0x30);
+ } else {
+ /* 1st try */
+ _pi_lcd_command(gpio_dev, 0x03);
+ task_sleep(USEC(4500)); /* wait for 4.1ms */
+
+ /* 2nd try */
+ _pi_lcd_command(gpio_dev, 0x03);
+ task_sleep(USEC(4500)); /* wait for 4.1ms */
+
+ /* 3rd try */
+ _pi_lcd_command(gpio_dev, 0x03);
+ task_sleep(USEC(150)); /* wait for 100us */
+
+ /* Set 4bit interface */
+ _pi_lcd_command(gpio_dev, 0x02);
+ }
+
+ /* finally, set # lines, font size, etc. */
+ _pi_lcd_command(gpio_dev, (LCD_FUNCTION_SET | lcd_data.disp_func));
+
+ /* turn the display on with no cursor or blinking default */
+ lcd_data.disp_cntl = LCD_DISPLAY_ON | LCD_CURSOR_OFF | LCD_BLINK_OFF;
+ pi_lcd_display_on(gpio_dev);
+
+ /* clear it off */
+ pi_lcd_clear(gpio_dev);
+
+ /* Initialize to default text direction */
+ lcd_data.disp_mode = LCD_ENTRY_LEFT | LCD_ENTRY_SHIFT_DECREMENT;
+ /* set the entry mode */
+ _pi_lcd_command(gpio_dev, LCD_ENTRY_MODE_SET | lcd_data.disp_mode);
+}
+
+void main(void)
+{
+ struct device *gpio_dev;
+
+ gpio_dev = device_get_binding(GPIO_DRV_NAME);
+ if (!gpio_dev) {
+ printk("Cannot find %s!\n", GPIO_DRV_NAME);
+ }
+
+ /* Setup GPIO output */
+ GPIO_PIN_CFG(gpio_dev, GPIO_PIN_PC25_E, GPIO_DIR_OUT);
+ GPIO_PIN_CFG(gpio_dev, GPIO_PIN_PC28_RS, GPIO_DIR_OUT);
+ GPIO_PIN_CFG(gpio_dev, GPIO_PIN_PC12_D0, GPIO_DIR_OUT);
+ GPIO_PIN_CFG(gpio_dev, GPIO_PIN_PC13_D1, GPIO_DIR_OUT);
+ GPIO_PIN_CFG(gpio_dev, GPIO_PIN_PC14_D2, GPIO_DIR_OUT);
+ GPIO_PIN_CFG(gpio_dev, GPIO_PIN_PC15_D3, GPIO_DIR_OUT);
+ GPIO_PIN_CFG(gpio_dev, GPIO_PIN_PC24_D4, GPIO_DIR_OUT);
+ GPIO_PIN_CFG(gpio_dev, GPIO_PIN_PC23_D5, GPIO_DIR_OUT);
+ GPIO_PIN_CFG(gpio_dev, GPIO_PIN_PC22_D6, GPIO_DIR_OUT);
+ GPIO_PIN_CFG(gpio_dev, GPIO_PIN_PC21_D7, GPIO_DIR_OUT);
+
+ printk("LCD Init\n");
+ pi_lcd_init(gpio_dev, 20, 4, LCD_5x8_DOTS);
+
+ /* Clear display */
+ pi_lcd_clear(gpio_dev);
+
+ while (1) {
+ printk("Page 1: message\n");
+
+ pi_lcd_string(gpio_dev, "********************");
+ pi_lcd_set_cursor(gpio_dev, 0, 1);
+ pi_lcd_string(gpio_dev, "Arduino Due");
+ pi_lcd_right_to_left(gpio_dev);
+ pi_lcd_set_cursor(gpio_dev, 15, 2);
+ pi_lcd_string(gpio_dev, "yalpsiD DCL 4x02");
+ pi_lcd_set_cursor(gpio_dev, 19, 3);
+ pi_lcd_left_to_right(gpio_dev);
+ pi_lcd_string(gpio_dev, "********************");
+ task_sleep(SECONDS(3));
+
+ /* Clear display */
+ pi_lcd_clear(gpio_dev);
+
+ printk("Page 2: message\n");
+
+ pi_lcd_scroll_right(gpio_dev);
+ pi_lcd_string(gpio_dev, "-------------------");
+ pi_lcd_set_cursor(gpio_dev, 0, 1);
+ pi_lcd_scroll_right(gpio_dev);
+ pi_lcd_string(gpio_dev, "Zephyr Rocks!");
+ pi_lcd_set_cursor(gpio_dev, 0, 2);
+ pi_lcd_string(gpio_dev, "My super RTOS");
+ pi_lcd_set_cursor(gpio_dev, 0, 3);
+ pi_lcd_string(gpio_dev, "-------------------");
+ task_sleep(SECONDS(3));
+
+ /* Clear display */
+ pi_lcd_clear(gpio_dev);
+
+ printk("Page 3: message\n");
+
+ pi_lcd_set_cursor(gpio_dev, 0, 3);
+ pi_lcd_string(gpio_dev, "--------------------");
+ pi_lcd_home(gpio_dev);
+ pi_lcd_string(gpio_dev, "--------HOME--------");
+ pi_lcd_set_cursor(gpio_dev, 0, 1);
+ pi_lcd_string(gpio_dev, "I am home!");
+ pi_lcd_set_cursor(gpio_dev, 0, 2);
+ pi_lcd_string(gpio_dev, "");
+ task_sleep(SECONDS(3));
+
+ /* Clear display */
+ pi_lcd_clear(gpio_dev);
+ }
+}
