initial commit

Makefile

@@ -0,0 +1,21 @@
+#MCU = msp430g2553
+MCU = msp430g2452
+
+clean:
+	rm -f main.elf main.lst lcd.o
+
+all: clean flash
+
+flash: compile
+	mspdebug rf2500 "prog main.elf"
+
+lcd:
+	msp430-gcc -Os -Wall -mmcu=$(MCU) -c lcd.c
+
+compile: lcd
+	msp430-gcc -Os -Wall -mmcu=$(MCU) -o main.elf main.c lcd.o
+	msp430-objdump -DS main.elf > main.lst
+	msp430-objdump -h main.elf
+	msp430-size main.elf
+
+.PHONY: all

README.md

@@ -0,0 +1,3 @@
+# MSP430 LCD
+
+A MSP430 lcd library in 4 bit mode.

lcd.c

@@ -0,0 +1,124 @@
+#include <msp430.h>
+#include <stdint.h>
+#include "lcd_config.h"
+#include "lcd.h"
+
+uint8_t lcd_pins[4] = {LCD_D4, LCD_D5, LCD_D6, LCD_D7};
+
+void lcd_delay_ms(uint16_t t) {
+  uint16_t i, j;
+  for (i = 0; i < (LCD_FCPU/1000); i++) {
+    for (j = 0; j < t; j++) {
+      nop();
+    }
+  }
+}
+
+void lcd_delay_us(uint16_t t) {
+  uint16_t i;
+  for (i = 0; i < (LCD_FCPU/1000000) * t; i++) {
+    nop();
+  }
+}
+
+void lcd_send4(uint8_t data) {
+	uint8_t i;
+  LCD_PORT |= LCD_EN;
+	for (i = 0; i < 4; i++) {
+		if (data & (1 << i)){
+			LCD_PORT |= lcd_pins[i];
+		} else {
+			LCD_PORT &= ~lcd_pins[i];
+		}
+	}
+  lcd_delay_us(1);
+  LCD_PORT &= ~LCD_EN;
+  LCD_PORT &= ~(LCD_DATA_PINS);
+  lcd_delay_us(1);
+}
+
+void lcd_send(uint8_t cmd, uint8_t data) {
+  LCD_PORT &= ~(LCD_RS | LCD_EN | LCD_DATA_PINS);
+
+  if (cmd & LCD_DATA) {
+    LCD_PORT |= LCD_RS;
+  }
+
+  lcd_send4(data >> 4);
+
+  if (cmd & LCD_CMD) {
+    lcd_delay_ms(5);
+  } else {
+    lcd_delay_us(1);
+  }
+
+  lcd_send4(data & 0x0F);
+
+  if (cmd & LCD_DATA) {
+    LCD_PORT &= ~LCD_RS;
+  }
+
+  lcd_delay_us(200);
+}
+
+void lcd_char(uint8_t data) {
+  lcd_send(LCD_DATA, data);
+}
+
+void lcd_cmd(uint8_t data) {
+  lcd_send(LCD_CMD, data);
+}
+
+uint8_t lcd_write(const char *str) {
+  uint8_t i = 0;
+  while (*str) {
+    lcd_char(*str++);
+    i++;
+  }
+  return i;
+}
+
+void lcd_writeln(const char *str) {
+  uint8_t i = lcd_write(str);
+	while(i++ < LCD_COLUMNS) {
+		lcd_char(' ');
+	}
+}
+
+void lcd_init(void) {
+  LCD_DIR |= LCD_RS | LCD_EN | LCD_DATA_PINS;
+  LCD_PORT &= ~(LCD_RS | LCD_EN | LCD_DATA_PINS);
+
+  lcd_delay_ms(20); // give lcd time to startup
+
+  lcd_send4(0x03);
+  lcd_delay_ms(5);
+
+  if (LCD_MODE == LCD_MODE_4) {
+    lcd_send4(0x02);
+    lcd_delay_us(37);
+  }
+
+  lcd_cmd(0x28);
+  lcd_cmd(0x01);
+  lcd_cmd(0x06);
+  lcd_delay_us(1200);
+  lcd_cmd(0x0C);
+}
+
+void lcd_go(uint8_t row, uint8_t col) {
+  if (row == 4) {
+    lcd_cmd(LCD_LINE_4 + col);
+	} else if (row == 3) {
+    lcd_cmd(LCD_LINE_3 + col);
+	} else if (row == 2) {
+    lcd_cmd(LCD_LINE_2 + col);
+	} else {
+    lcd_cmd(LCD_LINE_1 + col);
+  }
+}
+
+void lcd_go_line(uint8_t line) {
+  lcd_go(line, 0);
+}
+

lcd.h

@@ -0,0 +1,68 @@
+#ifndef __LCD_H__
+#define __LCD_H__
+#include "lcd_config.h"
+
+#ifndef LCD_PORT
+	#error "LCD_PORT not defined!"
+#endif
+
+#ifndef LCD_DIR
+	#error "LCD_DIR not defined!"
+#endif
+
+#ifndef LCD_RS
+	#error "LCD_RS not defined!"
+#endif
+
+#ifndef LCD_EN
+	#error "LCD_EN not defined!"
+#endif
+
+#ifndef LCD_D4
+	#error "LCD_D4 not defined!"
+#endif
+
+#ifndef LCD_D5
+	#error "LCD_D5 not defined!"
+#endif
+
+#ifndef LCD_D6
+	#error "LCD_D6 not defined!"
+#endif
+
+#ifndef LCD_D7
+	#error "LCD_D7 not defined!"
+#endif
+
+#ifndef LCD_COLUMNS
+#define LCD_COLUMNS 16
+#endif
+
+#ifndef LCD_ROWS
+#define LCD_ROWS 2
+#endif
+
+#define LCD_MODE_4 4
+
+#ifndef LCD_MODE
+#define LCD_MODE LCD_MODE_4
+#endif
+
+#define LCD_DATA_PINS LCD_D4 | LCD_D5 | LCD_D6 | LCD_D7
+#define LCD_CMD 0
+#define LCD_DATA 1
+
+#define LCD_HOME 0x80
+#define LCD_LINE_1 LCD_HOME
+#define LCD_LINE_2 LCD_HOME + 0x40
+#define LCD_LINE_3 LCD_HOME + 0x60
+#define LCD_LINE_4 LCD_HOME + 0x20
+
+void lcd_init(void);
+void lcd_writeln(const char *str);
+uint8_t lcd_write(const char *str);
+void lcd_go(uint8_t row, uint8_t col);
+void lcd_go_line(uint8_t line);
+void lcd_delay_ms(uint16_t t);
+void lcd_delay_us(uint16_t t);
+#endif // __LCD_H__

lcd_config.h

@@ -0,0 +1,22 @@
+/*
+ * Define pins and ports here
+ */
+
+#define LCD_PORT P1OUT
+#define LCD_DIR P1DIR
+
+#define LCD_RS BIT0
+#define LCD_EN BIT1
+
+#define LCD_D4 BIT4
+#define LCD_D5 BIT5
+#define LCD_D6 BIT6
+#define LCD_D7 BIT7
+#define LCD_FCPU 8000000
+
+
+// how many rows and colums?
+// default is 16x2
+
+// #define LCD_COLUMNS 16
+// #define LCD_ROWS 2

main.c

@@ -0,0 +1,18 @@
+#include <msp430.h>
+#include <stdint.h>
+#include "lcd.h"
+
+int main(void) {
+	WDTCTL = WDTPW + WDTHOLD;
+	DCOCTL = CALDCO_8MHZ;
+	BCSCTL1 = CALBC1_8MHZ;
+
+  lcd_init();
+  lcd_go_line(1);
+  lcd_writeln("Hello");
+  lcd_go_line(2);
+  lcd_writeln("World");
+  _BIS_SR(LPM3_bits);
+	while (1) {}
+	return 0;
+}