file cleanup, better text, documentation

1 files changed, 188 insertions, 0 deletions

diff --git a/old/lcd.c b/old/lcd.c
new file mode 100644
index 0000000..8229041
--- /dev/null
+++ b/old/lcd.c
@@ -0,0 +1,188 @@
+/**
+ * @file lcd.c
+ * A basic library for writing a 16x2 text LCD.
+ *
+ * Copyright (C) 2018 Clyne Sullivan
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <lcd.h>
+#include <clock.h>
+#include <gpio.h>
+#include <string.h>
+
+//#define USE_DELAY
+
+#define LCD_D0 GPIO_PORT(A, 0)
+#define LCD_D1 GPIO_PORT(A, 1)
+#define LCD_D2 GPIO_PORT(A, 4)
+#define LCD_D3 GPIO_PORT(B, 0)
+#define LCD_D4 GPIO_PORT(C, 1)
+#define LCD_D5 GPIO_PORT(C, 0)
+#define LCD_D6 GPIO_PORT(C, 2)
+#define LCD_D7 GPIO_PORT(C, 3)
+#define LCD_E  GPIO_PORT(C, 12)
+#define LCD_RS GPIO_PORT(C, 10)
+
+#define lcd_data() gpio_dout(LCD_RS, 1)
+
+void lcd_pulse(void)
+{
+	gpio_dout(LCD_E, 1);
+#ifdef USE_DELAY
+	delay(1);
+#else
+	for (uint16_t i = 0; i < 10000; i++)
+		asm("");
+#endif // USE_DELAY
+	gpio_dout(LCD_E, 0);
+}
+
+void lcd_byte(uint8_t byte)
+{
+	gpio_dout(LCD_D0, byte & 0x01);
+	gpio_dout(LCD_D1, byte & 0x02);
+	gpio_dout(LCD_D2, byte & 0x04);
+	gpio_dout(LCD_D3, byte & 0x08);
+	gpio_dout(LCD_D4, byte & 0x10);
+	gpio_dout(LCD_D5, byte & 0x20);
+	gpio_dout(LCD_D6, byte & 0x40);
+	gpio_dout(LCD_D7, byte & 0x80);
+}
+
+void lcd_cmd(uint8_t cmd)
+{
+	gpio_dout(LCD_RS, 0);
+	lcd_byte(cmd);
+	lcd_pulse();
+}
+
+void lcd_putchar(int c)
+{
+	lcd_data();
+	lcd_byte((uint8_t)c);
+	lcd_pulse();
+}
+
+static int lcd_index = 0;
+void lcd_puts(const char *s)
+{
+	lcd_cmd(0x06);
+	while (*s) {
+		lcd_putchar(*s++);
+		if (++lcd_index == 0x10) {
+			lcd_cmd(0x80 | 0x40);
+		} else if (lcd_index == 0x20) {
+			lcd_cmd(0x80);
+			lcd_index = 0;
+		}
+	}
+}
+
+extern char *itoa(int n, int base);
+void lcd_puti(int i)
+{
+	lcd_puts(itoa(i, 10));
+}
+
+void lcd_puth(int h)
+{
+	lcd_puts(itoa(h, 16));
+}
+
+void lcd_putb(uint8_t b)
+{
+	lcd_puts(itoa(b, 2));
+}
+
+void lcd_clear(void)
+{
+	lcd_cmd(0x01);
+	delay(2);
+	lcd_index = 0;
+}
+
+void lcd_init(void)
+{
+	gpio_mode(LCD_D0, OUTPUT);
+	gpio_mode(LCD_D1, OUTPUT);
+	gpio_mode(LCD_D2, OUTPUT);
+	gpio_mode(LCD_D3, OUTPUT);
+	gpio_mode(LCD_D4, OUTPUT);
+	gpio_mode(LCD_D5, OUTPUT);
+	gpio_mode(LCD_D6, OUTPUT);
+	gpio_mode(LCD_D7, OUTPUT);
+	gpio_mode(LCD_E,  OUTPUT);
+	gpio_mode(LCD_RS, OUTPUT);
+	gpio_dout(LCD_D0, 0);
+	gpio_dout(LCD_D1, 0);
+	gpio_dout(LCD_D2, 0);
+	gpio_dout(LCD_D3, 0);
+	gpio_dout(LCD_D4, 0);
+	gpio_dout(LCD_D5, 0);
+	gpio_dout(LCD_D6, 0);
+	gpio_dout(LCD_D7, 0);
+	gpio_dout(LCD_E,  0);
+	gpio_dout(LCD_RS, 0);
+
+	lcd_cmd(0x38);
+	lcd_cmd(0x10);
+	lcd_cmd(0x0D);
+	delay(5);
+	lcd_clear();
+}
+
+/**
+ * Task code
+ */
+
+volatile int bufpos = 0;
+volatile char buf[32];
+volatile uint8_t using = 0;
+
+void lcd_clearbuf(void)
+{
+	bufpos = 0;
+	for (int i = 0; i < 32; i++)
+		buf[i] = 0;
+}
+
+void lcd_put(const char *s)
+{
+	int len = strlen(s);
+	int i;
+
+	using = 1;
+	for (i = 0; i < len; bufpos++, i++) {
+		if (bufpos > 31)
+			bufpos = 0;
+		buf[bufpos] = s[i];
+	}
+	using = 0;
+}
+
+void lcd_handler(void)
+{
+	lcd_init();
+	lcd_clearbuf();
+
+	while (1) {
+		if (!using && buf[0] != '\0') {
+			lcd_puts(buf);
+			lcd_clearbuf();
+		}
+		delay(100);
+	}
+}