589 lines
		
	
	
	
		
			16 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			589 lines
		
	
	
	
		
			16 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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| #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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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
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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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| #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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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; 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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| 
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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(); 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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| 
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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
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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;
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|   sync_recv();
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|   bits = serial_read_chunk(&pecount,7);
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|   tid = bits>>3;
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|   bits = (bits&7) != nibble_bits_count(tid);
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|   if( bits || pecount> 0 || tid > Transaction_table_size ) {
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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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|   SSTD_t *trans = &Transaction_table[tid];
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|   serial_low(); // response step2 ack high->low
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| #endif
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| 
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|   // target send phase
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|   if( trans->target2initiator_buffer_size > 0 )
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|       serial_send_packet((uint8_t *)trans->target2initiator_buffer,
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|                          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 *)trans->initiator2target_buffer,
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|                                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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| #ifndef SERIAL_USE_MULTI_TRANSACTION
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| int  soft_serial_transaction(void) {
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|   SSTD_t *trans = Transaction_table;
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| #else
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| int  soft_serial_transaction(int sstd_index) {
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|   if( sstd_index > Transaction_table_size )
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|       return TRANSACTION_TYPE_ERROR;
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|   SSTD_t *trans = &Transaction_table[sstd_index];
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| #endif
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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();
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|   _delay_us(SLAVE_INT_WIDTH_US);
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| 
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| #ifndef SERIAL_USE_MULTI_TRANSACTION
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|   // wait for the target response
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|   serial_input_with_pullup();
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|   _delay_us(SLAVE_INT_RESPONSE_TIME);
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| 
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|   // check if the target is present
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|   if (serial_read_pin()) {
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|     // target failed to pull the line low, assume not present
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|     serial_output();
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|     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)
 | 
