added some examples, shortened some lcd functions

examples/Makefile

@@ -11,14 +11,14 @@ EFUSE = 0x05
 
 ## === Source files ===
 # Main C file
-MAIN = uart_isr.c
+MAIN = lcd_test.c
 # Extra C files in this folder
 LOCAL_SOURCE =
 
 # Library directory (with C files)
 EXTRA_SOURCE_DIR = lib/
 # C files in the library directory
-EXTRA_SOURCE_FILES = uart.c
+EXTRA_SOURCE_FILES = uart.c lcd.c
 
 
 ## === Programmer ===

examples/lcd_config.h

@@ -0,0 +1,13 @@
+#pragma once
+
+// Pin config file for LCD.
+
+#include "lib/arduino_pins.h"
+
+#define LCD_RS D2
+#define LCD_RW D3
+#define LCD_E  D4
+#define LCD_D4 D5
+#define LCD_D5 D6
+#define LCD_D6 D7
+#define LCD_D7 D8

examples/lcd_test.c

@@ -0,0 +1,58 @@
+//
+// Example of basic LCD usage
+//
+
+#include <avr/io.h>
+#include <avr/pgmspace.h>
+#include <util/delay.h>
+
+#include "lib/calc.h"
+#include "lib/lcd.h"
+
+// Bytes for custom glyph
+
+// Here's a good glyph generator you can use:
+//     http://omerk.github.io/lcdchargen/
+
+const uint8_t glyph[] PROGMEM = {
+	0b00000,
+	0b00111,
+	0b01101,
+	0b11101,
+	0b10001,
+	0b10001,
+	0b10001,
+	0b11111
+};
+
+
+void main()
+{
+	lcd_init();
+
+	// Define custom glyph at character 0
+	lcd_glyph_pgm(0, glyph);
+
+	// After writing a glyph, the address is changed
+	// So we need to fix that:
+	lcd_xy(0, 0);
+
+	// Print a string
+	lcd_puts("Hello");
+
+	// Use _pgm for strings in program memory
+	// Here we print string at position xy
+	lcd_puts_xy_pgm(0, 1, PSTR("String from PGM "));
+
+	// print the custom glyph
+	lcd_putc(0);
+
+	// enable blink/bar cursor type
+	lcd_cursor(CURSOR_BOTH);
+
+	lcd_puts_xy(5, 2, "Third line?");
+	lcd_puts_xy(3, 3, "Fourth line!");
+
+	// end
+	while(1);
+}

examples/uart_isr.c

@@ -1,8 +1,11 @@
+//
+// Example of UART with interrupts
+//
+
 #include <avr/io.h>
 #include <util/delay.h>
 #include <avr/pgmspace.h>
 #include <avr/interrupt.h>
-#include <stdbool.h>
 #include <stdint.h>
 #include <stdlib.h>
 

examples/uart_simple.c

@@ -1,8 +1,11 @@
+//
+// Example of basic UART usage
+//
+
 #include <avr/io.h>
 #include <util/delay.h>
 #include <avr/pgmspace.h>
 #include <avr/interrupt.h>
-#include <stdbool.h>
 #include <stdint.h>
 #include <stdlib.h>
 
@@ -21,8 +24,8 @@ void main()
 	// Printing a string
 	uart_puts("Simple UART example!\r\n");
 
-	// You can put your string literals in the program memory
-	// and use the _pgm variant:
+	// Use _pgm for strings in program memory
+	// (PSTR macro is defined in avr/pgmspace.h)
 	uart_puts_pgm(PSTR("Program memory string example\r\n"));
 
 	// print a char. This is an alias for uart_tx
@@ -32,24 +35,26 @@ void main()
 	uart_nl();
 
 	// Printing numbers is also easy
-	// Look in the library file for more info
+	// Look in `uart.h` for more info
 	uart_putn(123);
 	uart_nl();
 
-	// Print int as float (adds decimal point)
+	// Print int as float (adds decimal point at 4th place from the end)
 	uart_puti(31415, 4);
 	uart_nl();
 
 
-
 	// --- receive example ---
 
 	// Example of listening for input
 	while(1) {
+
 		// If something is received
 		if (uart_rx_ready()) {
+
 			// Get the received byte
 			char c = uart_rx();
+
 			// Send it back, twice
 			uart_tx(c);
 			uart_tx(c);