590 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			C
		
	
	
		
			Executable File
		
	
	
	
	
			
		
		
	
	
			590 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			C
		
	
	
		
			Executable File
		
	
	
	
	
/*
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 * WARNING: be careful changing this code, it is very timing dependent
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 *
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 * 2018-10-28 checked
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 *  avr-gcc 4.9.2
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 *  avr-gcc 5.4.0
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 *  avr-gcc 7.3.0
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 */
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#ifndef F_CPU
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#define F_CPU 16000000
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#endif
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#include <avr/io.h>
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#include <avr/interrupt.h>
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#include <util/delay.h>
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#include <stddef.h>
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#include <stdbool.h>
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#include "serial.h"
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#ifdef SOFT_SERIAL_PIN
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#ifdef __AVR_ATmega32U4__
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  // if using ATmega32U4 I2C, can not use PD0 and PD1 in soft serial.
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  #ifdef USE_I2C
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    #if SOFT_SERIAL_PIN == D0 || SOFT_SERIAL_PIN == D1
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      #error Using ATmega32U4 I2C, so can not use PD0, PD1
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    #endif
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  #endif
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  #if SOFT_SERIAL_PIN >= D0 && SOFT_SERIAL_PIN <= D3
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    #define SERIAL_PIN_DDR   DDRD
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    #define SERIAL_PIN_PORT  PORTD
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    #define SERIAL_PIN_INPUT PIND
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    #if SOFT_SERIAL_PIN == D0
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      #define SERIAL_PIN_MASK _BV(PD0)
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      #define EIMSK_BIT       _BV(INT0)
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      #define EICRx_BIT       (~(_BV(ISC00) | _BV(ISC01)))
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      #define SERIAL_PIN_INTERRUPT INT0_vect
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    #elif  SOFT_SERIAL_PIN == D1
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      #define SERIAL_PIN_MASK _BV(PD1)
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      #define EIMSK_BIT       _BV(INT1)
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      #define EICRx_BIT       (~(_BV(ISC10) | _BV(ISC11)))
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      #define SERIAL_PIN_INTERRUPT INT1_vect
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    #elif  SOFT_SERIAL_PIN == D2
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      #define SERIAL_PIN_MASK _BV(PD2)
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      #define EIMSK_BIT       _BV(INT2)
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      #define EICRx_BIT       (~(_BV(ISC20) | _BV(ISC21)))
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      #define SERIAL_PIN_INTERRUPT INT2_vect
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    #elif  SOFT_SERIAL_PIN == D3
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      #define SERIAL_PIN_MASK _BV(PD3)
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      #define EIMSK_BIT       _BV(INT3)
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      #define EICRx_BIT       (~(_BV(ISC30) | _BV(ISC31)))
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      #define SERIAL_PIN_INTERRUPT INT3_vect
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    #endif
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  #elif  SOFT_SERIAL_PIN == E6
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    #define SERIAL_PIN_DDR   DDRE
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    #define SERIAL_PIN_PORT  PORTE
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    #define SERIAL_PIN_INPUT PINE
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    #define SERIAL_PIN_MASK  _BV(PE6)
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    #define EIMSK_BIT        _BV(INT6)
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    #define EICRx_BIT        (~(_BV(ISC60) | _BV(ISC61)))
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    #define SERIAL_PIN_INTERRUPT INT6_vect
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  #else
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  #error invalid SOFT_SERIAL_PIN value
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  #endif
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#else
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 #error serial.c now support ATmega32U4 only
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#endif
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//////////////// for backward compatibility ////////////////////////////////
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#ifndef SERIAL_USE_MULTI_TRANSACTION
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/* --- USE Simple API (OLD API, compatible with let's split serial.c) */
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  #if SERIAL_SLAVE_BUFFER_LENGTH > 0
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  uint8_t volatile serial_slave_buffer[SERIAL_SLAVE_BUFFER_LENGTH] = {0};
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  #endif
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  #if SERIAL_MASTER_BUFFER_LENGTH > 0
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  uint8_t volatile serial_master_buffer[SERIAL_MASTER_BUFFER_LENGTH] = {0};
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  #endif
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  uint8_t volatile status0 = 0;
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SSTD_t transactions[] = {
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    { (uint8_t *)&status0,
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  #if SERIAL_MASTER_BUFFER_LENGTH > 0
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      sizeof(serial_master_buffer), (uint8_t *)serial_master_buffer,
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  #else
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      0, (uint8_t *)NULL,
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  #endif
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  #if SERIAL_SLAVE_BUFFER_LENGTH > 0
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      sizeof(serial_slave_buffer), (uint8_t *)serial_slave_buffer
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  #else
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      0, (uint8_t *)NULL,
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  #endif
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  }
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};
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void serial_master_init(void)
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{ soft_serial_initiator_init(transactions, TID_LIMIT(transactions)); }
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void serial_slave_init(void)
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{ soft_serial_target_init(transactions, TID_LIMIT(transactions)); }
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// 0 => no error
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// 1 => slave did not respond
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// 2 => checksum error
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int serial_update_buffers()
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{
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    int result;
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    result = soft_serial_transaction();
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    return result;
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}
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#endif // end of Simple API (OLD API, compatible with let's split serial.c)
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////////////////////////////////////////////////////////////////////////////
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#define ALWAYS_INLINE __attribute__((always_inline))
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#define NO_INLINE __attribute__((noinline))
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#define _delay_sub_us(x)    __builtin_avr_delay_cycles(x)
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// parity check
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#define ODD_PARITY 1
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#define EVEN_PARITY 0
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#define PARITY EVEN_PARITY
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#ifdef SERIAL_DELAY
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  // custom setup in config.h
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  // #define TID_SEND_ADJUST 2
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  // #define SERIAL_DELAY 6             // micro sec
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  // #define READ_WRITE_START_ADJUST 30 // cycles
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  // #define READ_WRITE_WIDTH_ADJUST 8 // cycles
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#else
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// ============ Standard setups ============
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#ifndef SELECT_SOFT_SERIAL_SPEED
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#define SELECT_SOFT_SERIAL_SPEED 1
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//  0: about 189kbps
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//  1: about 137kbps (default)
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//  2: about 75kbps
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//  3: about 39kbps
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//  4: about 26kbps
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//  5: about 20kbps
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#endif
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#if __GNUC__ < 6
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  #define TID_SEND_ADJUST 14
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#else
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  #define TID_SEND_ADJUST 2
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#endif
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#if SELECT_SOFT_SERIAL_SPEED == 0
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  // Very High speed
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  #define SERIAL_DELAY 4             // micro sec
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  #if __GNUC__ < 6
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    #define READ_WRITE_START_ADJUST 33 // cycles
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    #define READ_WRITE_WIDTH_ADJUST 3 // cycles
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  #else
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    #define READ_WRITE_START_ADJUST 34 // cycles
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    #define READ_WRITE_WIDTH_ADJUST 7 // cycles
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  #endif
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#elif SELECT_SOFT_SERIAL_SPEED == 1
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  // High speed
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  #define SERIAL_DELAY 6             // micro sec
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  #if __GNUC__ < 6
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    #define READ_WRITE_START_ADJUST 30 // cycles
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    #define READ_WRITE_WIDTH_ADJUST 3 // cycles
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  #else
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    #define READ_WRITE_START_ADJUST 33 // cycles
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    #define READ_WRITE_WIDTH_ADJUST 7 // cycles
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  #endif
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#elif SELECT_SOFT_SERIAL_SPEED == 2
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  // Middle speed
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  #define SERIAL_DELAY 12            // micro sec
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  #define READ_WRITE_START_ADJUST 30 // cycles
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  #if __GNUC__ < 6
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    #define READ_WRITE_WIDTH_ADJUST 3 // cycles
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  #else
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    #define READ_WRITE_WIDTH_ADJUST 7 // cycles
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  #endif
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#elif SELECT_SOFT_SERIAL_SPEED == 3
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  // Low speed
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  #define SERIAL_DELAY 24            // micro sec
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  #define READ_WRITE_START_ADJUST 30 // cycles
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  #if __GNUC__ < 6
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    #define READ_WRITE_WIDTH_ADJUST 3 // cycles
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  #else
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    #define READ_WRITE_WIDTH_ADJUST 7 // cycles
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  #endif
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#elif SELECT_SOFT_SERIAL_SPEED == 4
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  // Very Low speed
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  #define SERIAL_DELAY 36            // micro sec
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  #define READ_WRITE_START_ADJUST 30 // cycles
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  #if __GNUC__ < 6
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    #define READ_WRITE_WIDTH_ADJUST 3 // cycles
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  #else
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    #define READ_WRITE_WIDTH_ADJUST 7 // cycles
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  #endif
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#elif SELECT_SOFT_SERIAL_SPEED == 5
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  // Ultra Low speed
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  #define SERIAL_DELAY 48            // micro sec
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  #define READ_WRITE_START_ADJUST 30 // cycles
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  #if __GNUC__ < 6
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    #define READ_WRITE_WIDTH_ADJUST 3 // cycles
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  #else
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    #define READ_WRITE_WIDTH_ADJUST 7 // cycles
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  #endif
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#else
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#error invalid SELECT_SOFT_SERIAL_SPEED value
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#endif /* SELECT_SOFT_SERIAL_SPEED */
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#endif /* SERIAL_DELAY */
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#define SERIAL_DELAY_HALF1 (SERIAL_DELAY/2)
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#define SERIAL_DELAY_HALF2 (SERIAL_DELAY - SERIAL_DELAY/2)
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#define SLAVE_INT_WIDTH_US 1
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#ifndef SERIAL_USE_MULTI_TRANSACTION
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  #define SLAVE_INT_RESPONSE_TIME SERIAL_DELAY
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#else
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  #define SLAVE_INT_ACK_WIDTH_UNIT 2
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  #define SLAVE_INT_ACK_WIDTH 4
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#endif
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static SSTD_t *Transaction_table = NULL;
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static uint8_t Transaction_table_size = 0;
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inline static void serial_delay(void) ALWAYS_INLINE;
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inline static
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void serial_delay(void) {
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  _delay_us(SERIAL_DELAY);
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}
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inline static void serial_delay_half1(void) ALWAYS_INLINE;
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inline static
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void serial_delay_half1(void) {
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  _delay_us(SERIAL_DELAY_HALF1);
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}
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inline static void serial_delay_half2(void) ALWAYS_INLINE;
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inline static
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void serial_delay_half2(void) {
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  _delay_us(SERIAL_DELAY_HALF2);
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}
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inline static void serial_output(void) ALWAYS_INLINE;
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inline static
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void serial_output(void) {
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  SERIAL_PIN_DDR |= SERIAL_PIN_MASK;
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}
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// make the serial pin an input with pull-up resistor
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inline static void serial_input_with_pullup(void) ALWAYS_INLINE;
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inline static
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void serial_input_with_pullup(void) {
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  SERIAL_PIN_DDR  &= ~SERIAL_PIN_MASK;
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  SERIAL_PIN_PORT |= SERIAL_PIN_MASK;
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}
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inline static uint8_t serial_read_pin(void) ALWAYS_INLINE;
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inline static
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uint8_t serial_read_pin(void) {
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  return !!(SERIAL_PIN_INPUT & SERIAL_PIN_MASK);
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}
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inline static void serial_low(void) ALWAYS_INLINE;
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inline static
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void serial_low(void) {
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  SERIAL_PIN_PORT &= ~SERIAL_PIN_MASK;
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}
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inline static void serial_high(void) ALWAYS_INLINE;
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inline static
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void serial_high(void) {
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  SERIAL_PIN_PORT |= SERIAL_PIN_MASK;
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}
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void soft_serial_initiator_init(SSTD_t *sstd_table, int sstd_table_size)
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{
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    Transaction_table = sstd_table;
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    Transaction_table_size = (uint8_t)sstd_table_size;
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    serial_output();
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    serial_high();
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}
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void soft_serial_target_init(SSTD_t *sstd_table, int sstd_table_size)
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{
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    Transaction_table = sstd_table;
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    Transaction_table_size = (uint8_t)sstd_table_size;
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    serial_input_with_pullup();
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    // Enable INT0-INT3,INT6
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    EIMSK |= EIMSK_BIT;
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#if SERIAL_PIN_MASK == _BV(PE6)
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    // Trigger on falling edge of INT6
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    EICRB &= EICRx_BIT;
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#else
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    // Trigger on falling edge of INT0-INT3
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    EICRA &= EICRx_BIT;
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#endif
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}
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// Used by the sender to synchronize timing with the reciver.
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static void sync_recv(void) NO_INLINE;
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static
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void sync_recv(void) {
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  for (uint8_t i = 0; i < SERIAL_DELAY*5 && serial_read_pin(); i++ ) {
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  }
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  // This shouldn't hang if the target disconnects because the
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  // serial line will float to high if the target does disconnect.
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  while (!serial_read_pin());
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}
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// Used by the reciver to send a synchronization signal to the sender.
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static void sync_send(void) NO_INLINE;
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static
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void sync_send(void) {
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  serial_low();
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  serial_delay();
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  serial_high();
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}
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// Reads a byte from the serial line
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static uint8_t serial_read_chunk(uint8_t *pterrcount, uint8_t bit) NO_INLINE;
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static uint8_t serial_read_chunk(uint8_t *pterrcount, uint8_t bit) {
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    uint8_t byte, i, p, pb;
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  _delay_sub_us(READ_WRITE_START_ADJUST);
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  for( i = 0, byte = 0, p = PARITY; i < bit; i++ ) {
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      serial_delay_half1();   // read the middle of pulses
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      if( serial_read_pin() ) {
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          byte = (byte << 1) | 1; p ^= 1;
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      } else {
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          byte = (byte << 1) | 0; p ^= 0;
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      }
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      _delay_sub_us(READ_WRITE_WIDTH_ADJUST);
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      serial_delay_half2();
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  }
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  /* recive parity bit */
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  serial_delay_half1();   // read the middle of pulses
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  pb = serial_read_pin();
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  _delay_sub_us(READ_WRITE_WIDTH_ADJUST);
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  serial_delay_half2();
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  *pterrcount += (p != pb)? 1 : 0;
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  return byte;
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}
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// Sends a byte with MSB ordering
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void serial_write_chunk(uint8_t data, uint8_t bit) NO_INLINE;
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void serial_write_chunk(uint8_t data, uint8_t bit) {
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    uint8_t b, p;
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    for( p = PARITY, b = 1<<(bit-1); b ; b >>= 1) {
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        if(data & b) {
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            serial_high(); p ^= 1;
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        } else {
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            serial_low();  p ^= 0;
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        }
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        serial_delay();
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    }
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    /* send parity bit */
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    if(p & 1) { serial_high(); }
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    else      { serial_low(); }
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    serial_delay();
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    serial_low(); // sync_send() / senc_recv() need raise edge
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}
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static void serial_send_packet(uint8_t *buffer, uint8_t size) NO_INLINE;
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static
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void serial_send_packet(uint8_t *buffer, uint8_t size) {
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  for (uint8_t i = 0; i < size; ++i) {
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    uint8_t data;
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    data = buffer[i];
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    sync_send();
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    serial_write_chunk(data,8);
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  }
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}
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static uint8_t serial_recive_packet(uint8_t *buffer, uint8_t size) NO_INLINE;
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static
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uint8_t serial_recive_packet(uint8_t *buffer, uint8_t size) {
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  uint8_t pecount = 0;
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  for (uint8_t i = 0; i < size; ++i) {
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    uint8_t data;
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    sync_recv();
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    data = serial_read_chunk(&pecount, 8);
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    buffer[i] = data;
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  }
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  return pecount == 0;
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}
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inline static
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void change_sender2reciver(void) {
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    sync_send();          //0
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    serial_delay_half1(); //1
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    serial_low();         //2
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    serial_input_with_pullup(); //2
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    serial_delay_half1(); //3
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}
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inline static
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void change_reciver2sender(void) {
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    sync_recv();     //0
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    serial_delay();  //1
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    serial_low();    //3
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    serial_output(); //3
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    serial_delay_half1(); //4
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}
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static inline uint8_t nibble_bits_count(uint8_t bits)
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{
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    bits = (bits & 0x5) + (bits >> 1 & 0x5);
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    bits = (bits & 0x3) + (bits >> 2 & 0x3);
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    return bits;
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}
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// interrupt handle to be used by the target device
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ISR(SERIAL_PIN_INTERRUPT) {
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#ifndef SERIAL_USE_MULTI_TRANSACTION
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  serial_low();
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  serial_output();
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  SSTD_t *trans = Transaction_table;
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#else
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  // recive transaction table index
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  uint8_t tid, bits;
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  uint8_t pecount = 0;
 | 
						|
  sync_recv();
 | 
						|
  bits = serial_read_chunk(&pecount,7);
 | 
						|
  tid = bits>>3;
 | 
						|
  bits = (bits&7) != nibble_bits_count(tid);
 | 
						|
  if( bits || pecount> 0 || tid > Transaction_table_size ) {
 | 
						|
      return;
 | 
						|
  }
 | 
						|
  serial_delay_half1();
 | 
						|
 | 
						|
  serial_high(); // response step1 low->high
 | 
						|
  serial_output();
 | 
						|
  _delay_sub_us(SLAVE_INT_ACK_WIDTH_UNIT*SLAVE_INT_ACK_WIDTH);
 | 
						|
  SSTD_t *trans = &Transaction_table[tid];
 | 
						|
  serial_low(); // response step2 ack high->low
 | 
						|
#endif
 | 
						|
 | 
						|
  // target send phase
 | 
						|
  if( trans->target2initiator_buffer_size > 0 )
 | 
						|
      serial_send_packet((uint8_t *)trans->target2initiator_buffer,
 | 
						|
                         trans->target2initiator_buffer_size);
 | 
						|
  // target switch to input
 | 
						|
  change_sender2reciver();
 | 
						|
 | 
						|
  // target recive phase
 | 
						|
  if( trans->initiator2target_buffer_size > 0 ) {
 | 
						|
      if (serial_recive_packet((uint8_t *)trans->initiator2target_buffer,
 | 
						|
                               trans->initiator2target_buffer_size) ) {
 | 
						|
          *trans->status = TRANSACTION_ACCEPTED;
 | 
						|
      } else {
 | 
						|
          *trans->status = TRANSACTION_DATA_ERROR;
 | 
						|
      }
 | 
						|
  } else {
 | 
						|
      *trans->status = TRANSACTION_ACCEPTED;
 | 
						|
  }
 | 
						|
 | 
						|
  sync_recv(); //weit initiator output to high
 | 
						|
}
 | 
						|
 | 
						|
/////////
 | 
						|
//  start transaction by initiator
 | 
						|
//
 | 
						|
// int  soft_serial_transaction(int sstd_index)
 | 
						|
//
 | 
						|
// Returns:
 | 
						|
//    TRANSACTION_END
 | 
						|
//    TRANSACTION_NO_RESPONSE
 | 
						|
//    TRANSACTION_DATA_ERROR
 | 
						|
// this code is very time dependent, so we need to disable interrupts
 | 
						|
#ifndef SERIAL_USE_MULTI_TRANSACTION
 | 
						|
int  soft_serial_transaction(void) {
 | 
						|
  SSTD_t *trans = Transaction_table;
 | 
						|
#else
 | 
						|
int  soft_serial_transaction(int sstd_index) {
 | 
						|
  if( sstd_index > Transaction_table_size )
 | 
						|
      return TRANSACTION_TYPE_ERROR;
 | 
						|
  SSTD_t *trans = &Transaction_table[sstd_index];
 | 
						|
#endif
 | 
						|
  cli();
 | 
						|
 | 
						|
  // signal to the target that we want to start a transaction
 | 
						|
  serial_output();
 | 
						|
  serial_low();
 | 
						|
  _delay_us(SLAVE_INT_WIDTH_US);
 | 
						|
 | 
						|
#ifndef SERIAL_USE_MULTI_TRANSACTION
 | 
						|
  // wait for the target response
 | 
						|
  serial_input_with_pullup();
 | 
						|
  _delay_us(SLAVE_INT_RESPONSE_TIME);
 | 
						|
 | 
						|
  // check if the target is present
 | 
						|
  if (serial_read_pin()) {
 | 
						|
    // target failed to pull the line low, assume not present
 | 
						|
    serial_output();
 | 
						|
    serial_high();
 | 
						|
    *trans->status = TRANSACTION_NO_RESPONSE;
 | 
						|
    sei();
 | 
						|
    return TRANSACTION_NO_RESPONSE;
 | 
						|
  }
 | 
						|
 | 
						|
#else
 | 
						|
  // send transaction table index
 | 
						|
  int tid = (sstd_index<<3) | (7 & nibble_bits_count(sstd_index));
 | 
						|
  sync_send();
 | 
						|
  _delay_sub_us(TID_SEND_ADJUST);
 | 
						|
  serial_write_chunk(tid, 7);
 | 
						|
  serial_delay_half1();
 | 
						|
 | 
						|
  // wait for the target response (step1 low->high)
 | 
						|
  serial_input_with_pullup();
 | 
						|
  while( !serial_read_pin() ) {
 | 
						|
      _delay_sub_us(2);
 | 
						|
  }
 | 
						|
 | 
						|
  // check if the target is present (step2 high->low)
 | 
						|
  for( int i = 0; serial_read_pin(); i++ ) {
 | 
						|
      if (i > SLAVE_INT_ACK_WIDTH + 1) {
 | 
						|
          // slave failed to pull the line low, assume not present
 | 
						|
          serial_output();
 | 
						|
          serial_high();
 | 
						|
          *trans->status = TRANSACTION_NO_RESPONSE;
 | 
						|
          sei();
 | 
						|
          return TRANSACTION_NO_RESPONSE;
 | 
						|
      }
 | 
						|
      _delay_sub_us(SLAVE_INT_ACK_WIDTH_UNIT);
 | 
						|
  }
 | 
						|
#endif
 | 
						|
 | 
						|
  // initiator recive phase
 | 
						|
  // if the target is present syncronize with it
 | 
						|
  if( trans->target2initiator_buffer_size > 0 ) {
 | 
						|
      if (!serial_recive_packet((uint8_t *)trans->target2initiator_buffer,
 | 
						|
                                trans->target2initiator_buffer_size) ) {
 | 
						|
          serial_output();
 | 
						|
          serial_high();
 | 
						|
          *trans->status = TRANSACTION_DATA_ERROR;
 | 
						|
          sei();
 | 
						|
          return TRANSACTION_DATA_ERROR;
 | 
						|
      }
 | 
						|
   }
 | 
						|
 | 
						|
  // initiator switch to output
 | 
						|
  change_reciver2sender();
 | 
						|
 | 
						|
  // initiator send phase
 | 
						|
  if( trans->initiator2target_buffer_size > 0 ) {
 | 
						|
      serial_send_packet((uint8_t *)trans->initiator2target_buffer,
 | 
						|
                         trans->initiator2target_buffer_size);
 | 
						|
  }
 | 
						|
 | 
						|
  // always, release the line when not in use
 | 
						|
  sync_send();
 | 
						|
 | 
						|
  *trans->status = TRANSACTION_END;
 | 
						|
  sei();
 | 
						|
  return TRANSACTION_END;
 | 
						|
}
 | 
						|
 | 
						|
#ifdef SERIAL_USE_MULTI_TRANSACTION
 | 
						|
int soft_serial_get_and_clean_status(int sstd_index) {
 | 
						|
    SSTD_t *trans = &Transaction_table[sstd_index];
 | 
						|
    cli();
 | 
						|
    int retval = *trans->status;
 | 
						|
    *trans->status = 0;;
 | 
						|
    sei();
 | 
						|
    return retval;
 | 
						|
}
 | 
						|
#endif
 | 
						|
 | 
						|
#endif
 | 
						|
 | 
						|
// Helix serial.c history
 | 
						|
//   2018-1-29 fork from let's split and add PD2, modify sync_recv() (#2308, bceffdefc)
 | 
						|
//   2018-6-28 bug fix master to slave comm and speed up (#3255, 1038bbef4)
 | 
						|
//             (adjusted with avr-gcc 4.9.2)
 | 
						|
//   2018-7-13 remove USE_SERIAL_PD2 macro (#3374, f30d6dd78)
 | 
						|
//             (adjusted with avr-gcc 4.9.2)
 | 
						|
//   2018-8-11 add support multi-type transaction (#3608, feb5e4aae)
 | 
						|
//             (adjusted with avr-gcc 4.9.2)
 | 
						|
//   2018-10-21 fix serial and RGB animation conflict (#4191, 4665e4fff)
 | 
						|
//             (adjusted with avr-gcc 7.3.0)
 | 
						|
//   2018-10-28 re-adjust compiler depend value of delay (#4269, 8517f8a66)
 | 
						|
//             (adjusted with avr-gcc 5.4.0, 7.3.0)
 |