extracted protos and macros to header file.

1602LCD_char_display.c

@@ -8,73 +8,7 @@
 #include <avr/interrupt.h>
 #include <avr/sleep.h>
 #include <util/delay.h>
-
-
-#define RS_PORT PORTD
-#define RS_PIN  PIND0
-#define RS_DDR  DDD0
-
-
-//#define RW_PORT PORTD
-//#define RW_PIN  PIND1
-//#define RW_DDR  DDD1
-
-
-#define ENA_PORT PORTD
-#define ENA_PIN  PIND1
-#define ENA_DDR  DDD1
-
-#define BIT4_PORT   PORTD
-#define BIT4_PIN    PIND4
-#define BIT4_DDR    DDD4
-
-
-#define BIT5_PORT   PORTD
-#define BIT5_PIN    PIND5
-#define BIT5_DDR    DDD5
-
-#define BIT6_PORT   PORTD
-#define BIT6_PIN    PIND6
-#define BIT6_DDR    DDD6
-
-#define BIT7_PORT   PORTD
-#define BIT7_PIN    PIND7
-#define BIT7_DDR    DDD7
-
-#define LED_PIN     PINC0
-#define LED_PORT    PORTC
-#define LED_DDR     DDC0
-
-//LCD CONNECTIONS:
-/*
- * VSS --> GND
- * VDD --> VCC
- * V0  --> POT --> GND
- * RS  --> PD0(AVR)
- * RW  --> GND
- * E   --> PD1(AVR)
- * D4  --> PD4(AVR)
- * D5  --> PD5(AVR)
- * D6  --> PD6(AVR)
- * D7  --> PD7(AVR)
- *
- * PURPOSE:
- * RS: register select,
- * RW: Read/Write select signal,
- * E:  Operation(data read/write) enable signal.
- * DB0~DB3: not used for 4bit operations.
- * DB4~DB7: high order three-state data lines.
- */
-
-
-//#############################
-//MACROS
-//#############################
-
-//already defined
-//#define _BV(bit) (1 << bit)
-#define setbit(port, bit) (port) |= (1 << (bit))
-#define clearbit(port, bit) (port) &= ~(1 << (bit))
+#include "1602LCD_char_display.h"
 
 
 
@@ -82,28 +16,6 @@
 //FUNCTION PROTOTYPES
 //#############################
 
-
-void init_lcd(void);
-void cmd_lcd(uint8_t cmd);
-void cmd_nibble_lcd(uint8_t cmd);
-void clear_lcd(void);                                                                                               
-static void led_blink(void);
-void set_lcd_one_line_(void);
-void set_lcd_two_line(void);
-void return_home_lcd(void);
-void turn_off_lcd(void);
-void turn_on_lcd(void);
-void set_cgram_lcd_address(uint8_t addr);
-void set_ddram_lcd_address(uint8_t addr);
-void write_lcd_address(uint8_t addr);
-void set_entry_mode_increment_lcd(void);
-void set_entry_mode_decrement_lcd(void);
-void shift_right_lcd(void);
-void shift_left_lcd(void);
-void bbs(void);
-void clear_buf_lcd();
-
-
 int main() {
     PORTD = 0x00;
     DDRD = 0xff;
@@ -158,18 +70,6 @@ int main() {
 //FUNCTIONS
 //#############################
 
-
-void bbs(void) {
-    _delay_ms(500);
-    write_lcd_address(0x42);
-    write_lcd_address(0x4f);
-    write_lcd_address(0x4f);
-    write_lcd_address(0x42);
-    write_lcd_address(0x49);
-    write_lcd_address(0x45);
-    write_lcd_address(0x53); 
-}
-
 /*
  * Input: none
  * Output: none

1602LCD_char_display.h

@@ -0,0 +1,97 @@
+#include <avr/io.h>
+#include <avr/interrupt.h>
+#include <avr/sleep.h>
+#include <util/delay.h>
+
+
+#define RS_PORT PORTD
+#define RS_PIN  PIND0
+#define RS_DDR  DDD0
+
+
+//#define RW_PORT PORTD
+//#define RW_PIN  PIND1
+//#define RW_DDR  DDD1
+
+
+#define ENA_PORT PORTD
+#define ENA_PIN  PIND1
+#define ENA_DDR  DDD1
+
+#define BIT4_PORT   PORTD
+#define BIT4_PIN    PIND4
+#define BIT4_DDR    DDD4
+
+
+#define BIT5_PORT   PORTD
+#define BIT5_PIN    PIND5
+#define BIT5_DDR    DDD5
+
+#define BIT6_PORT   PORTD
+#define BIT6_PIN    PIND6
+#define BIT6_DDR    DDD6
+
+#define BIT7_PORT   PORTD
+#define BIT7_PIN    PIND7
+#define BIT7_DDR    DDD7
+
+#define LED_PIN     PINC0
+#define LED_PORT    PORTC
+#define LED_DDR     DDC0
+
+//LCD CONNECTIONS:
+/*
+ * VSS --> GND
+ * VDD --> VCC
+ * V0  --> POT --> GND
+ * RS  --> PD0(AVR)
+ * RW  --> GND
+ * E   --> PD1(AVR)
+ * D4  --> PD4(AVR)
+ * D5  --> PD5(AVR)
+ * D6  --> PD6(AVR)
+ * D7  --> PD7(AVR)
+ *
+ * PURPOSE:
+ * RS: register select,
+ * RW: Read/Write select signal,
+ * E:  Operation(data read/write) enable signal.
+ * DB0~DB3: not used for 4bit operations.
+ * DB4~DB7: high order three-state data lines.
+ */
+
+
+//#############################
+//MACROS
+//#############################
+
+//already defined
+//#define _BV(bit) (1 << bit)
+#define setbit(port, bit) (port) |= (1 << (bit))
+#define clearbit(port, bit) (port) &= ~(1 << (bit))
+
+//#############################
+//FUNCTION PROTOTYPES
+//#############################
+
+
+void init_lcd(void);
+void cmd_lcd(uint8_t cmd);
+void cmd_nibble_lcd(uint8_t cmd);
+void clear_lcd(void);                                                                                               
+static void led_blink(void);
+void set_lcd_one_line_(void);
+void set_lcd_two_line(void);
+void return_home_lcd(void);
+void turn_off_lcd(void);
+void turn_on_lcd(void);
+void set_cgram_lcd_address(uint8_t addr);
+void set_ddram_lcd_address(uint8_t addr);
+void write_lcd_address(uint8_t addr);
+void set_entry_mode_increment_lcd(void);
+void set_entry_mode_decrement_lcd(void);
+void shift_right_lcd(void);
+void shift_left_lcd(void);
+void clear_buf_lcd();
+
+

README.md

@@ -23,20 +23,30 @@ ___
 ```C
 #include "AVR_ATMEGA_1602LCD.h"
 
-void lcd_begin() {
-    set_lcd_two_line();
-    return_home_lcd();
-    clear_lcd();
+void do_stuff() {
+    PORTD = 0x00;
+    DDRD = 0xff;
+    init_lcd();
     
-    //Do stuff.
+    return_home_lcd();
+    set_entry_mode_increment_lcd();
+   
+    //Refernce the datasheet for charecter codes. 
+    write_lcd_address(0x7f);    //Right pointing arrow 
+    
+    //wait a bit.
+    _delay_ms(1000);
+
+    //clear it up
+    clear_lcd();
+    return_home_lcd();
+
+    //Do more stuff...
 }
 ```
 
 ## RoadMap:
 
-1. define all functions for the data sheets instructions.
-2. Change cmd_lcd() function to only be called once instead of nibbles.
-3. Make functions port indapendant.
 4. ADD function to print strings
 5. ADD function to display bit images
 6. ADD function to act as a loading screen.
@@ -45,4 +55,13 @@ void lcd_begin() {
 9. ADD PWM control for backlight
 
 
+## ISSUES:
+
+Currently during powerloss events and initialization, long wire runs or 
+residual charge can cause the LCD to maintain memory for a shor duration.
+
+In 4bit mode it's possible to end up with a invalid "nibble" in the LCD memory
+in this case the system should power cycle the LCD unit assuming it's 
+controlled by the microcontroller.
+