forked from mirrors/qmk_userspace
Update split serial code to use driver pattern (#7990)
* Move avr serial code to drivers * Update src+= serial.c to driver pattern
This commit is contained in:
Joel Challis
GitHub
parent
4867a9b1e6
commit
e4a0f841e1
3 changed files with 8 additions and 2 deletions
508
drivers/avr/serial.c
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508
drivers/avr/serial.c
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/*
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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_AVR_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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# 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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# if SOFT_SERIAL_PIN >= D0 && SOFT_SERIAL_PIN <= D3
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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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# 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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# 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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# 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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# endif
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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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# 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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# 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 (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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# 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 void serial_delay(void) { _delay_us(SERIAL_DELAY); }
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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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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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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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// 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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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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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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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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void soft_serial_initiator_init(SSTD_t *sstd_table, int sstd_table_size) {
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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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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 SOFT_SERIAL_PIN == E6
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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 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 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;
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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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*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();
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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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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 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 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 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 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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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;
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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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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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// target send phase
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if (trans->target2initiator_buffer_size > 0) serial_send_packet((uint8_t *)trans->target2initiator_buffer, trans->target2initiator_buffer_size);
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// target switch to input
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change_sender2reciver();
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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, 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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sync_recv(); // weit initiator output to high
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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) 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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// 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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# 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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// 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();
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*trans->status = TRANSACTION_NO_RESPONSE;
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sei();
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return TRANSACTION_NO_RESPONSE;
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}
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# else
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// send transaction table index
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int tid = (sstd_index << 3) | (7 & nibble_bits_count(sstd_index));
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sync_send();
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_delay_sub_us(TID_SEND_ADJUST);
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serial_write_chunk(tid, 7);
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serial_delay_half1();
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// wait for the target response (step1 low->high)
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serial_input_with_pullup();
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while (!serial_read_pin()) {
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_delay_sub_us(2);
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}
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// check if the target is present (step2 high->low)
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for (int i = 0; serial_read_pin(); i++) {
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if (i > SLAVE_INT_ACK_WIDTH + 1) {
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// slave failed to pull the line low, assume not present
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serial_output();
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serial_high();
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*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)
|
||||
// 2018-12-17 copy to TOP/quantum/split_common/ and remove backward compatibility code (#4669)
|
||||
Loading…
Add table
Add a link
Reference in a new issue