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authorDavid A. Mellis <d.mellis@arduino.cc>2008-04-19 03:31:36 +0000
committerDavid A. Mellis <d.mellis@arduino.cc>2008-04-19 03:31:36 +0000
commit2d5bc015fbd70befc08c2295630ff06770e9d7c8 (patch)
tree0b2b41ab905ce47067d3365861aced34f89caa9c /libraries/LiquidCrystal/LiquidCrystal.cpp
parente8465fbb4500ed3968e7a06c2d75a5b3f1841b8e (diff)
Adding LiquidCrystal library.
Diffstat (limited to 'libraries/LiquidCrystal/LiquidCrystal.cpp')
-rwxr-xr-xlibraries/LiquidCrystal/LiquidCrystal.cpp128
1 files changed, 128 insertions, 0 deletions
diff --git a/libraries/LiquidCrystal/LiquidCrystal.cpp b/libraries/LiquidCrystal/LiquidCrystal.cpp
new file mode 100755
index 0000000..c5acc85
--- /dev/null
+++ b/libraries/LiquidCrystal/LiquidCrystal.cpp
@@ -0,0 +1,128 @@
+#include "LiquidCrystal.h"
+
+#include <stdio.h>
+#include <string.h>
+#include <inttypes.h>
+#include "WProgram.h"
+
+// When the display powers up, it is configured as follows:
+//
+// 1. Display clear
+// 2. Function set:
+// DL = 1; 8-bit interface data
+// N = 0; 1-line display
+// F = 0; 5x8 dot character font
+// 3. Display on/off control:
+// D = 0; Display off
+// C = 0; Cursor off
+// B = 0; Blinking off
+// 4. Entry mode set:
+// I/D = 1; Increment by 1
+// S = 0; No shift
+//
+// Note, however, that resetting the Arduino doesn't reset the LCD, so we
+// can't assume that its in that state when a sketch starts (and the
+// LiquidCrystal constructor is called).
+
+LiquidCrystal::LiquidCrystal(uint8_t rs, uint8_t rw, uint8_t enable,
+ uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3,
+ uint8_t d4, uint8_t d5, uint8_t d6, uint8_t d7) : Print(baseWrite),
+ _four_bit_mode(0), _rs_pin(rs), _rw_pin(rw), _enable_pin(enable)
+{
+ _data_pins[0] = d0;
+ _data_pins[1] = d1;
+ _data_pins[2] = d2;
+ _data_pins[3] = d3;
+ _data_pins[4] = d4;
+ _data_pins[5] = d5;
+ _data_pins[6] = d6;
+ _data_pins[7] = d7;
+
+ pinMode(_rs_pin, OUTPUT);
+ pinMode(_rw_pin, OUTPUT);
+ pinMode(_enable_pin, OUTPUT);
+
+ for (int i = 0; i < 8; i++)
+ pinMode(_data_pins[i], OUTPUT);
+
+ command(0x38); // function set: 8 bits, 1 line, 5x8 dots
+ command(0x0C); // display control: turn display on, cursor off, no blinking
+ command(0x06); // entry mode set: increment automatically, display shift, right shift
+ clear();
+}
+
+LiquidCrystal::LiquidCrystal(uint8_t rs, uint8_t rw, uint8_t enable,
+ uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3) : Print(baseWrite),
+ _four_bit_mode(1), _rs_pin(rs), _rw_pin(rw), _enable_pin(enable)
+{
+ _data_pins[0] = d0;
+ _data_pins[1] = d1;
+ _data_pins[2] = d2;
+ _data_pins[3] = d3;
+
+ pinMode(_rs_pin, OUTPUT);
+ pinMode(_rw_pin, OUTPUT);
+ pinMode(_enable_pin, OUTPUT);
+
+ for (int i = 0; i < 4; i++)
+ pinMode(_data_pins[i], OUTPUT);
+
+ command(0x28); // function set: 4 bits, 1 line, 5x8 dots
+ command(0x0C); // display control: turn display on, cursor off, no blinking
+ command(0x06); // entry mode set: increment automatically, display shift, right shift
+ clear();
+}
+
+void LiquidCrystal::clear()
+{
+ command(0x01); // clear display, set cursor position to zero
+ delayMicroseconds(2000);
+}
+
+void LiquidCrystal::home()
+{
+ command(0x02); // set cursor position to zero
+ delayMicroseconds(2000);
+}
+
+void LiquidCrystal::setCursor(int col, int row)
+{
+ int row_offsets[] = { 0x00, 0x40, 0x14, 0x54 };
+ command(0x80 | (col + row_offsets[row]));
+}
+
+void LiquidCrystal::command(int value) {
+ write(value, LOW);
+}
+
+void LiquidCrystal::write(int value, int mode) {
+ digitalWrite(_rs_pin, mode);
+ digitalWrite(_rw_pin, LOW);
+
+ if (_four_bit_mode) {
+ for (int i = 0; i < 4; i++) {
+ digitalWrite(_data_pins[i], (value >> (i + 4)) & 0x01);
+ }
+
+ digitalWrite(_enable_pin, HIGH);
+ digitalWrite(_enable_pin, LOW);
+
+ for (int i = 0; i < 4; i++) {
+ digitalWrite(_data_pins[i], (value >> i) & 0x01);
+ }
+
+ digitalWrite(_enable_pin, HIGH);
+ digitalWrite(_enable_pin, LOW);
+ } else {
+ for (int i = 0; i < 8; i++) {
+ digitalWrite(_data_pins[i], (value >> i) & 0x01);
+ }
+
+ digitalWrite(_enable_pin, HIGH);
+ digitalWrite(_enable_pin, LOW);
+ }
+}
+
+void baseWrite(uint8_t value, void *instance) {
+ ((LiquidCrystal *) instance)->write(value);
+}