patch-2.4.19 linux-2.4.19/arch/mips/ddb5xxx/ddb5477/lcd44780.c

• Lines: 93
• Date: Fri Aug 2 17:39:43 2002
• Orig file: linux-2.4.18/arch/mips/ddb5xxx/ddb5477/lcd44780.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -urN linux-2.4.18/arch/mips/ddb5xxx/ddb5477/lcd44780.c linux-2.4.19/arch/mips/ddb5xxx/ddb5477/lcd44780.c
@@ -0,0 +1,92 @@
+/*
+ * lcd44780.c
+ * Simple "driver" for a memory-mapped 44780-style LCD display.
+ *
+ * Copyright 2001 Bradley D. LaRonde <brad@ltc.com>
+ *
+ * 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 2 of the  License, or (at your
+ * option) any later version.
+ *
+ */
+
+#define LCD44780_COMMAND   ((volatile unsigned char *)0xbe020000)
+#define LCD44780_DATA      ((volatile unsigned char *)0xbe020001)
+
+#define LCD44780_4BIT_1LINE        0x20
+#define LCD44780_4BIT_2LINE        0x28
+#define LCD44780_8BIT_1LINE        0x30
+#define LCD44780_8BIT_2LINE        0x38
+#define LCD44780_MODE_DEC          0x04
+#define LCD44780_MODE_DEC_SHIFT    0x05
+#define LCD44780_MODE_INC          0x06
+#define LCD44780_MODE_INC_SHIFT    0x07
+#define LCD44780_SCROLL_LEFT       0x18
+#define LCD44780_SCROLL_RIGHT      0x1e
+#define LCD44780_CURSOR_UNDERLINE  0x0e
+#define LCD44780_CURSOR_BLOCK      0x0f
+#define LCD44780_CURSOR_OFF        0x0c
+#define LCD44780_CLEAR             0x01
+#define LCD44780_BLANK             0x08
+#define LCD44780_RESTORE           0x0c  // Same as CURSOR_OFF
+#define LCD44780_HOME              0x02
+#define LCD44780_LEFT              0x10
+#define LCD44780_RIGHT             0x14
+
+void lcd44780_wait(void)
+{
+	int i, j;
+	for(i=0; i < 400; i++)
+		for(j=0; j < 10000; j++);
+}
+
+void lcd44780_command(unsigned char c)
+{
+	*LCD44780_COMMAND = c;
+	lcd44780_wait();
+}
+
+void lcd44780_data(unsigned char c)
+{
+	*LCD44780_DATA = c;
+	lcd44780_wait();
+}
+
+void lcd44780_puts(const char* s)
+{
+	int i,j;
+	int pos = 0;
+
+	lcd44780_command(LCD44780_CLEAR);
+	while(*s) {
+		lcd44780_data(*s);
+		s++;
+		pos++;
+		if (pos == 8) {
+		  /* We must write 32 of spaces to get cursor to 2nd line */
+		  for (j=0; j<32; j++) {
+		    lcd44780_data(' ');
+		  }
+		}
+		if (pos == 16) {
+		  /* We have filled all 16 character positions, so stop
+		     outputing data */
+		  break;
+		}
+	}
+#ifdef LCD44780_PUTS_PAUSE
+	for(i = 1; i < 2000; i++)
+		lcd44780_wait();
+#endif
+}
+
+void lcd44780_init(void)
+{
+	// The display on the RockHopper is physically a single
+	// 16 char line (two 8 char lines concatenated).  bdl
+	lcd44780_command(LCD44780_8BIT_2LINE);
+	lcd44780_command(LCD44780_MODE_INC);
+	lcd44780_command(LCD44780_CURSOR_BLOCK);
+	lcd44780_command(LCD44780_CLEAR);
+}