Merge remote-tracking branch 'refs/remotes/origin/master'

emb/buttons.cpp

+#include "buttons.hpp"
+#include "uart.hpp"
+#include "time.hpp"
+#include <avr/io.h>
+
+static bool lastStateA = false;
+static bool lastStateB = false;
+static uint32_t lastMillisA = 0;
+static uint32_t lastMillisB = 0;
+
+void initButtons()
+{
+    DDRC &= ~(1 << DDC5) & ~(1 << DDC4);    // set PC5 and PC4 as inputs
+    PORTC |= (1 << PORTC5) | (1 << PORTC4); // enable pullups
+}
+
+void updateButtons()
+{
+    uint32_t currMillis = getCurrentMillis();
+    
+    bool currStateA = (PINC & (1 << PINC5));
+    bool currStateB = (PINC & (1 << PINC4));
+    
+    if (currStateA != lastStateA)
+    {
+        lastStateA = currStateA;
+        
+        if (!currStateA && (currMillis - lastMillisA) > 50) 
+            writeUart('a');
+        
+        lastMillisA = currMillis;
+    }
+    
+    if (currStateB != lastStateB)
+    {
+        lastStateB = currStateB;
+        
+        if (!currStateB && (currMillis - lastMillisB) > 50)
+            writeUart('b');
+        
+        lastMillisB = currMillis;
+    }
+}

emb/buttons.hpp

+#ifndef BUTTONS_H
+#define BUTTONS_H
+
+/**
+ * Initialises the button logic.
+ */
+void initButtons();
+
+/**
+ * Updates the button logic.
+ * Should be called periodically.
+ */
+void updateButtons();
+
+#endif /* BUTTONS_H */

emb/display.cpp

+#include <util/delay.h>
+#include <avr/io.h>
+
+// commands
+#define LCD_CLEARDISPLAY 0x01
+#define LCD_RETURNHOME 0x02
+#define LCD_ENTRYMODESET 0x04
+#define LCD_DISPLAYCONTROL 0x08
+#define LCD_CURSORSHIFT 0x10
+#define LCD_FUNCTIONSET 0x20
+#define LCD_SETCGRAMADDR 0x40
+#define LCD_SETDDRAMADDR 0x80
+
+// flags for display entry mode
+#define LCD_ENTRYRIGHT 0x00
+#define LCD_ENTRYLEFT 0x02
+#define LCD_ENTRYSHIFTINCREMENT 0x01
+#define LCD_ENTRYSHIFTDECREMENT 0x00
+
+// flags for display on/off control
+#define LCD_DISPLAYON 0x04
+#define LCD_DISPLAYOFF 0x00
+#define LCD_CURSORON 0x02
+#define LCD_CURSOROFF 0x00
+#define LCD_BLINKON 0x01
+#define LCD_BLINKOFF 0x00
+
+// flags for display/cursor shift
+#define LCD_DISPLAYMOVE 0x08
+#define LCD_CURSORMOVE 0x00
+#define LCD_MOVERIGHT 0x04
+#define LCD_MOVELEFT 0x00
+
+// flags for function set
+#define LCD_8BITMODE 0x10
+#define LCD_4BITMODE 0x00
+#define LCD_2LINE 0x08
+#define LCD_1LINE 0x00
+#define LCD_5x10DOTS 0x04
+#define LCD_5x8DOTS 0x00
+
+#define RS_lo() PORTD &= ~(1 << PORTD2)
+#define RS_hi() PORTD |=  (1 << PORTD2)
+#define EN_lo() PORTD &= ~(1 << PORTD3)
+#define EN_hi() PORTD |=  (1 << PORTD3)
+
+void send(uint8_t value)
+{
+    PORTD &= 0x0F;
+    PORTB &= 0xF0;
+    
+    PORTD |= value & 0xF0;
+    PORTB |= value & 0x0F;
+    
+    EN_hi();
+    _delay_us(1);
+    EN_lo();
+    _delay_us(50);
+}
+
+void command(uint8_t value)
+{
+    RS_lo();
+    send(value);
+}
+
+void writeDisplay(uint8_t value)
+{
+    RS_hi();
+    send(value);
+}
+
+void clearDisplay()
+{
+    command(LCD_CLEARDISPLAY);
+    _delay_us(2000);
+}
+
+void initDisplay()
+{
+    DDRD |= 0xF0 | (1 << DDD3) | (1 << DDD2);
+    DDRB |= 0x0F;
+    
+    uint8_t _displayfunction = LCD_8BITMODE | LCD_2LINE | LCD_1LINE | LCD_5x8DOTS;
+    
+    _delay_ms(50);
+    
+    RS_lo();
+    EN_lo();
+    
+    command(LCD_FUNCTIONSET | _displayfunction);
+    _delay_us(4500);
+    command(LCD_FUNCTIONSET | _displayfunction);
+    _delay_us(150);
+    command(LCD_FUNCTIONSET | _displayfunction);
+    command(LCD_FUNCTIONSET | _displayfunction);
+    
+    uint8_t _displaycontrol = LCD_DISPLAYON | LCD_CURSOROFF | LCD_BLINKOFF;
+    command(LCD_DISPLAYCONTROL | _displaycontrol);
+    
+    clearDisplay();
+    
+    uint8_t _displaymode = LCD_ENTRYLEFT | LCD_ENTRYSHIFTDECREMENT;
+    command(LCD_ENTRYMODESET | _displaymode);
+}
+
+void setDisplayCursor(uint8_t col, uint8_t row)
+{
+    row &= 1;
+    
+    command(LCD_SETDDRAMADDR | (col + row * 0x40));
+}
+

emb/display.hpp

+#ifndef DISPLAY_H
+#define DISPLAY_H
+
+void initDisplay();
+void writeDisplay(uint8_t value);
+void setDisplayCursor(uint8_t col, uint8_t row);
+void clearDisplay();
+
+#endif /* DISPLAY_H */

emb/servos.cpp

@@ -21,9 +21,9 @@ struct Servo
 };
 
 static Servo servos[NUM_SERVOS] = {
-    { &PORTB, &DDRB, (1 << PB2), 0, 0 },
-    { &PORTB, &DDRB, (1 << PB3), 0, 0 },
-    { &PORTB, &DDRB, (1 << PB4), 0, 0 }
+    { &PORTC, &DDRC, (1 << PB0), 0, 0 },
+    { &PORTC, &DDRC, (1 << PB1), 0, 0 },
+    { &PORTC, &DDRC, (1 << PB2), 0, 0 }
 };
 
 static uint16_t orderedValues[NUM_SERVOS];  // current servo values in ascending order

emb/uart.cpp

@@ -12,7 +12,6 @@ void initUart()
     
     UCSR0A = (1 << U2X0);  // double transmission speed
     UCSR0B = (1 << RXCIE0) // enable RX complete interrupt
-           | (1 << UDRIE0) // enable data register empty interrupt
            | (1 << RXEN0)  // enable receiver
            | (1 << TXEN0); // enable transmitter
     UCSR0C = (0 << UMSEL01) | (0 << UMSEL00) // asynchronous USART
@@ -25,12 +24,14 @@ void initUart()
     sei();
 }
 
-ISR(USART_RX_vect)
+void writeUart(uint8_t value)
 {
-    uart_add_ch(UDR0);
+    while (!(UCSR0A & (1 << UDRE0)));
+    
+    UDR0 = value;
 }
 
-ISR(USART_UDRE_vect)
+ISR(USART_RX_vect)
 {
-    // nothing to do right now
+    uart_add_ch(UDR0);
 }

emb/uart.hpp

 #ifndef UART_H
 #define UART_H
 
+#include <stdint.h>
+
 /**
  * Initialises the UART logic.
  */
 void initUart();
 
+/**
+ * Writes a character to the UART port.
+ */
+void writeUart(uint8_t value);
+
 #endif /* UART_H */