Technical_Notes

//  The Pin map below is copyright by the Arduino people.  I include it here so I can remember stuff as I code.
// ATMEL ATMEGA8 & 168 / ARDUINO
// //
// //                  +-\/-+
// //            PC6  1|    |28  PC5 (AI 5)
// //      (D 0) PD0  2|    |27  PC4 (AI 4)
// //      (D 1) PD1  3|    |26  PC3 (AI 3)
// //      (D 2) PD2  4|    |25  PC2 (AI 2)
// // PWM+ (D 3) PD3  5|    |24  PC1 (AI 1)
// //      (D 4) PD4  6|    |23  PC0 (AI 0)
// //            VCC  7|    |22  GND
// //            GND  8|    |21  AREF
// //            PB6  9|    |20  AVCC
// //            PB7 10|    |19  PB5 (D 13)
// // PWM+ (D 5) PD5 11|    |18  PB4 (D 12)
// // PWM+ (D 6) PD6 12|    |17  PB3 (D 11) PWM
// //      (D 7) PD7 13|    |16  PB2 (D 10) PWM
// //      (D 8) PB0 14|    |15  PB1 (D 9) PWM
// //                  +----+
// 
// const static uint8_t A0 = 14;
// const static uint8_t A1 = 15;
// const static uint8_t A2 = 16;
// const static uint8_t A3 = 17;
// const static uint8_t A4 = 18;
// const static uint8_t A5 = 19;
// const static uint8_t A6 = 20;
// const static uint8_t A7 = 21;
//
// Macros to find pins:
// #define digitalPinToPort(P) ( pgm_read_byte( digital_pin_to_port_PGM + (P) ) )
// #define digitalPinToBitMask(P) ( pgm_read_byte( digital_pin_to_bit_mask_PGM + (P) ) )
// #define digitalPinToTimer(P) ( pgm_read_byte( digital_pin_to_timer_PGM + (P) ) )
// #define analogInPinToBit(P) (P)
// #define portOutputRegister(P) ( (volatile uint8_t *)( pgm_read_word( port_to_output_PGM + (P))) )
// #define portInputRegister(P) ( (volatile uint8_t *)( pgm_read_word( port_to_input_PGM + (P))) )
// #define portModeRegister(P) ( (volatile uint8_t *)( pgm_read_word( port_to_mode_PGM + (P))) )

/*
struct encoder {
    volatile uint8_t* port;

    uint8_t bitA;
    uint8_t bitB;

    uint8_t turning;    // Flag to keep track of turning state
    int8_t clicks;      // Counter to indicate cumulative clicks in either direction
    int8_t direction;   // indicator

    char id;

    encoder *next;
};*/