first commit

incl/lcd.rs

@@ -0,0 +1,100 @@
+use embedded_hal::i2c::I2c;
+use std::thread::sleep;
+use std::time::Duration;
+
+pub struct Lcd<I: I2c> {
+    i2c: I,
+    addr: u8,
+    backlight: bool,
+}
+
+impl<I: I2c> Lcd<I> {
+    const RS: u8 = 0b001;
+    const EN: u8 = 0b100;
+    const BL: u8 = 0b1000;
+
+    pub fn new(i2c: I, addr: u8) -> Result<Self, I::Error> {
+        let mut lcd = Self { i2c, addr, backlight: true };
+        lcd.init()?;
+        Ok(lcd)
+    }
+
+    fn write_nibble(&mut self, nibble: u8, rs: u8) -> Result<(), I::Error> {
+        let bl = if self.backlight { Self::BL } else { 0 };
+        let data = nibble | rs | bl;
+        self.i2c.write(self.addr, &[data | Self::EN])?;
+        sleep(Duration::from_micros(1));
+        self.i2c.write(self.addr, &[data & !Self::EN])?;
+        sleep(Duration::from_micros(50));
+        Ok(())
+    }
+
+    fn write_byte(&mut self, byte: u8, rs: u8) -> Result<(), I::Error> {
+        self.write_nibble(byte & 0xF0, rs)?;
+        self.write_nibble((byte & 0x0F) << 4, rs)?;
+        Ok(())
+    }
+
+    fn cmd(&mut self, c: u8) -> Result<(), I::Error> {
+        self.write_byte(c, 0)?;
+        if c <= 0x03 {
+            sleep(Duration::from_millis(2));
+        }
+        Ok(())
+    }
+
+    fn data(&mut self, d: u8) -> Result<(), I::Error> {
+        self.write_byte(d, Self::RS)
+    }
+
+    fn init(&mut self) -> Result<(), I::Error> {
+        sleep(Duration::from_millis(50));
+        for _ in 0..3 {
+            self.write_nibble(0x30, 0)?;
+            sleep(Duration::from_millis(5));
+        }
+        self.write_nibble(0x20, 0)?;
+        sleep(Duration::from_millis(1));
+
+        self.cmd(0x28)?;
+        self.cmd(0x0C)?;
+        self.cmd(0x06)?;
+        self.cmd(0x01)?;
+        sleep(Duration::from_millis(2));
+        Ok(())
+    }
+
+    pub fn clear(&mut self) -> Result<(), I::Error> {
+        self.cmd(0x01)?;
+        sleep(Duration::from_millis(2));
+        Ok(())
+    }
+
+    pub fn set_cursor(&mut self, col: u8, row: u8) -> Result<(), I::Error> {
+        let addr = match row {
+            0 => 0x00,
+            1 => 0x40,
+            2 => 0x14,
+            3 => 0x54,
+            _ => 0x00,
+        };
+        self.cmd(0x80 | (addr + col))
+    }
+
+    pub fn create_char(&mut self, location: u8, data: &[u8; 8]) -> Result<(), I::Error> {
+        self.cmd(0x40 | (location << 3))?;
+        for &b in data {
+            self.data(b)?;
+        }
+        self.set_cursor(0, 0)
+    }
+
+
+
+    pub fn print(&mut self, s: &str) -> Result<(), I::Error> {
+        for b in s.bytes() {
+            self.data(b)?;
+        }
+        Ok(())
+    }
+}