530 lines
		
	
	
		
			18 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			530 lines
		
	
	
		
			18 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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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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| 
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| #ifndef F_CPU
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| #    define F_CPU 16000000
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| #endif
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| 
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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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| 
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| #ifdef SOFT_SERIAL_PIN
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| 
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| #    if !(defined(__AVR_AT90USB646__) || defined(__AVR_AT90USB647__) || defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB1287__) || defined(__AVR_AT90USB162__) || defined(__AVR_ATmega16U2__) || defined(__AVR_ATmega32U2__) || defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__))
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| #        error serial.c is not supported for the currently selected MCU
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| #    endif
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| // if using ATmega32U4/2, AT90USBxxx I2C, can not use PD0 and PD1 in soft serial.
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| #    if defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__) || defined(__AVR_AT90USB646__) || defined(__AVR_AT90USB647__) || defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB1287__)
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| #        if defined(USE_AVR_I2C) && (SOFT_SERIAL_PIN == D0 || SOFT_SERIAL_PIN == D1)
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| #            error Using I2C, so can not use PD0, PD1
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| #        endif
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| #    endif
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| // PD0..PD3, common config
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| #    if SOFT_SERIAL_PIN == D0
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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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| #        define EICRx EICRA
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| #    elif SOFT_SERIAL_PIN == D1
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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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| #        define EICRx EICRA
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| #    elif SOFT_SERIAL_PIN == D2
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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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| #        define EICRx EICRA
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| #    elif SOFT_SERIAL_PIN == D3
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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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| #        define EICRx EICRA
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| #    endif
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| 
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| // ATmegaxxU2/AT90USB162 specific config
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| #    if defined(__AVR_ATmega16U2__) || defined(__AVR_ATmega32U2__) || defined(__AVR_AT90USB162__)
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| // PD4(INT5), PD6(INT6), PD7(INT7), PC7(INT4)
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| #        if SOFT_SERIAL_PIN == D4
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| #            define EIMSK_BIT _BV(INT5)
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| #            define EICRx_BIT (~(_BV(ISC50) | _BV(ISC51)))
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| #            define SERIAL_PIN_INTERRUPT INT5_vect
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| #            define EICRx EICRB
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| #        elif SOFT_SERIAL_PIN == D6
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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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| #            define EICRx EICRB
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| #        elif SOFT_SERIAL_PIN == D7
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| #            define EIMSK_BIT _BV(INT7)
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| #            define EICRx_BIT (~(_BV(ISC70) | _BV(ISC71)))
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| #            define SERIAL_PIN_INTERRUPT INT7_vect
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| #            define EICRx EICRB
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| #        elif SOFT_SERIAL_PIN == C7
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| #            define EIMSK_BIT _BV(INT4)
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| #            define EICRx_BIT (~(_BV(ISC40) | _BV(ISC41)))
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| #            define SERIAL_PIN_INTERRUPT INT4_vect
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| #            define EICRx EICRB
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| #        endif
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| #    endif
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| 
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| // ATmegaxxU4 specific config
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| #    if defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__)
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| // PE6(INT6)
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| #        if SOFT_SERIAL_PIN == E6
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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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| #            define EICRx EICRB
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| #        endif
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| #    endif
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| 
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| // AT90USBxxx specific config
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| #    if defined(__AVR_AT90USB646__) || defined(__AVR_AT90USB647__) || defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB1287__)
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| // PE4..PE7(INT4..INT7)
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| #        if SOFT_SERIAL_PIN == E4
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| #            define EIMSK_BIT _BV(INT4)
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| #            define EICRx_BIT (~(_BV(ISC40) | _BV(ISC41)))
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| #            define SERIAL_PIN_INTERRUPT INT4_vect
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| #            define EICRx EICRB
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| #        elif SOFT_SERIAL_PIN == E5
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| #            define EIMSK_BIT _BV(INT5)
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| #            define EICRx_BIT (~(_BV(ISC50) | _BV(ISC51)))
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| #            define SERIAL_PIN_INTERRUPT INT5_vect
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| #            define EICRx EICRB
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| #        elif SOFT_SERIAL_PIN == E6
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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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| #            define EICRx EICRB
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| #        elif SOFT_SERIAL_PIN == E7
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| #            define EIMSK_BIT _BV(INT7)
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| #            define EICRx_BIT (~(_BV(ISC70) | _BV(ISC71)))
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| #            define SERIAL_PIN_INTERRUPT INT7_vect
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| #            define EICRx EICRB
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| #        endif
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| #    endif
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| 
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| #    ifndef SERIAL_PIN_INTERRUPT
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| #        error invalid SOFT_SERIAL_PIN value
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| #    endif
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| 
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| #    define setPinInputHigh(pin) (DDRx_ADDRESS(pin) &= ~_BV((pin)&0xF), PORTx_ADDRESS(pin) |= _BV((pin)&0xF))
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| #    define setPinOutput(pin) (DDRx_ADDRESS(pin) |= _BV((pin)&0xF))
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| #    define writePinHigh(pin) (PORTx_ADDRESS(pin) |= _BV((pin)&0xF))
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| #    define writePinLow(pin) (PORTx_ADDRESS(pin) &= ~_BV((pin)&0xF))
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| #    define readPin(pin) ((bool)(PINx_ADDRESS(pin) & _BV((pin)&0xF)))
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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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| 
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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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| 
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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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| 
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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 (Experimental only)
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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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| 
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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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| 
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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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| 
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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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| 
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| #    define SLAVE_INT_WIDTH_US 1
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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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| 
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| inline static void serial_delay(void) ALWAYS_INLINE;
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| inline static void serial_delay(void) { _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 void serial_delay_half1(void) { _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 void serial_delay_half2(void) { _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 void serial_output(void) { setPinOutput(SOFT_SERIAL_PIN); }
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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 void serial_input_with_pullup(void) { setPinInputHigh(SOFT_SERIAL_PIN); }
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| 
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| inline static uint8_t serial_read_pin(void) ALWAYS_INLINE;
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| inline static uint8_t serial_read_pin(void) { return !!readPin(SOFT_SERIAL_PIN); }
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| 
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| inline static void serial_low(void) ALWAYS_INLINE;
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| inline static void serial_low(void) { writePinLow(SOFT_SERIAL_PIN); }
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| 
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| inline static void serial_high(void) ALWAYS_INLINE;
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| inline static void serial_high(void) { writePinHigh(SOFT_SERIAL_PIN); }
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| 
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| void soft_serial_initiator_init(void) {
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|     serial_output();
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|     serial_high();
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| }
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| 
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| void soft_serial_target_init(void) {
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|     serial_input_with_pullup();
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| 
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|     // Enable INT0-INT7
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|     EIMSK |= EIMSK_BIT;
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|     EICRx &= EICRx_BIT;
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| }
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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 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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| }
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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 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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| 
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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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| 
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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;
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|             p ^= 1;
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|         } else {
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|             byte = (byte << 1) | 0;
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|             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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| 
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|     *pterrcount += (p != pb) ? 1 : 0;
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| 
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|     return byte;
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| }
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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();
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|             p ^= 1;
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|         } else {
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|             serial_low();
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|             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) {
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|         serial_high();
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|     } else {
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|         serial_low();
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|     }
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|     serial_delay();
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| 
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|     serial_low();  // sync_send() / senc_recv() need raise edge
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| }
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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 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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| 
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| static uint8_t serial_recive_packet(uint8_t *buffer, uint8_t size) NO_INLINE;
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| static 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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| 
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| inline static 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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| 
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| inline static 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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| 
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| static inline uint8_t nibble_bits_count(uint8_t bits) {
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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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| 
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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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|     // recive transaction table index
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|     uint8_t tid, bits;
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|     uint8_t pecount = 0;
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|     sync_recv();
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|     bits = serial_read_chunk(&pecount, 8);
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|     tid  = bits >> 3;
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|     bits = (bits & 7) != (nibble_bits_count(tid) & 7);
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|     if (bits || pecount > 0 || tid > NUM_TOTAL_TRANSACTIONS) {
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|         return;
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|     }
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|     serial_delay_half1();
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| 
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|     serial_high();  // response step1 low->high
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|     serial_output();
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|     _delay_sub_us(SLAVE_INT_ACK_WIDTH_UNIT * SLAVE_INT_ACK_WIDTH);
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|     split_transaction_desc_t *trans = &split_transaction_table[tid];
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|     serial_low();  // response step2 ack high->low
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| 
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|     // If the transaction has a callback, we can execute it now
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|     if (trans->slave_callback) {
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|         trans->slave_callback(trans->initiator2target_buffer_size, split_trans_initiator2target_buffer(trans), trans->target2initiator_buffer_size, split_trans_target2initiator_buffer(trans));
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|     }
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| 
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|     // target send phase
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|     if (trans->target2initiator_buffer_size > 0) serial_send_packet((uint8_t *)split_trans_target2initiator_buffer(trans), trans->target2initiator_buffer_size);
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|     // target switch to input
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|     change_sender2reciver();
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| 
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|     // target recive phase
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|     if (trans->initiator2target_buffer_size > 0) {
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|         if (serial_recive_packet((uint8_t *)split_trans_initiator2target_buffer(trans), trans->initiator2target_buffer_size)) {
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|             *trans->status = TRANSACTION_ACCEPTED;
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|         } else {
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|             *trans->status = TRANSACTION_DATA_ERROR;
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|         }
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|     } else {
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|         *trans->status = TRANSACTION_ACCEPTED;
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|     }
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| 
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|     sync_recv();  // weit initiator output to high
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| }
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| 
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| /////////
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| //  start transaction by initiator
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| //
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| // int  soft_serial_transaction(int sstd_index)
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| //
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| // Returns:
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| //    TRANSACTION_END
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| //    TRANSACTION_NO_RESPONSE
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| //    TRANSACTION_DATA_ERROR
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| // this code is very time dependent, so we need to disable interrupts
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| int soft_serial_transaction(int sstd_index) {
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|     if (sstd_index > NUM_TOTAL_TRANSACTIONS) return TRANSACTION_TYPE_ERROR;
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|     split_transaction_desc_t *trans = &split_transaction_table[sstd_index];
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| 
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|     if (!trans->status) return TRANSACTION_TYPE_ERROR;  // not registered
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| 
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|     cli();
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| 
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|     // signal to the target that we want to start a transaction
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|     serial_output();
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|     serial_low();
 | |
|     _delay_us(SLAVE_INT_WIDTH_US);
 | |
| 
 | |
|     // 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, 8);
 | |
|     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);
 | |
|     }
 | |
| 
 | |
|     // initiator recive phase
 | |
|     // if the target is present syncronize with it
 | |
|     if (trans->target2initiator_buffer_size > 0) {
 | |
|         if (!serial_recive_packet((uint8_t *)split_trans_target2initiator_buffer(trans), 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 *)split_trans_initiator2target_buffer(trans), trans->initiator2target_buffer_size);
 | |
|     }
 | |
| 
 | |
|     // always, release the line when not in use
 | |
|     sync_send();
 | |
| 
 | |
|     *trans->status = TRANSACTION_END;
 | |
|     sei();
 | |
|     return TRANSACTION_END;
 | |
| }
 | |
| 
 | |
| int soft_serial_get_and_clean_status(int sstd_index) {
 | |
|     split_transaction_desc_t *trans = &split_transaction_table[sstd_index];
 | |
|     cli();
 | |
|     int retval     = *trans->status;
 | |
|     *trans->status = 0;
 | |
|     ;
 | |
|     sei();
 | |
|     return retval;
 | |
| }
 | |
| #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)
 | |
| //   2018-12-17 copy to TOP/quantum/split_common/ and remove backward compatibility code (#4669)
 |