diff options
Diffstat (limited to 'drivers/avr/serial.c')
| -rw-r--r-- | drivers/avr/serial.c | 508 |
1 files changed, 508 insertions, 0 deletions
diff --git a/drivers/avr/serial.c b/drivers/avr/serial.c new file mode 100644 index 0000000000..c27cbfdd0a --- /dev/null +++ b/drivers/avr/serial.c @@ -0,0 +1,508 @@ +/* + * WARNING: be careful changing this code, it is very timing dependent + * + * 2018-10-28 checked + * avr-gcc 4.9.2 + * avr-gcc 5.4.0 + * avr-gcc 7.3.0 + */ + +#ifndef F_CPU +# define F_CPU 16000000 +#endif + +#include <avr/io.h> +#include <avr/interrupt.h> +#include <util/delay.h> +#include <stddef.h> +#include <stdbool.h> +#include "serial.h" + +#ifdef SOFT_SERIAL_PIN + +# ifdef __AVR_ATmega32U4__ +// if using ATmega32U4 I2C, can not use PD0 and PD1 in soft serial. +# ifdef USE_AVR_I2C +# if SOFT_SERIAL_PIN == D0 || SOFT_SERIAL_PIN == D1 +# error Using ATmega32U4 I2C, so can not use PD0, PD1 +# endif +# endif + +# define setPinInputHigh(pin) (DDRx_ADDRESS(pin) &= ~_BV((pin)&0xF), PORTx_ADDRESS(pin) |= _BV((pin)&0xF)) +# define setPinOutput(pin) (DDRx_ADDRESS(pin) |= _BV((pin)&0xF)) +# define writePinHigh(pin) (PORTx_ADDRESS(pin) |= _BV((pin)&0xF)) +# define writePinLow(pin) (PORTx_ADDRESS(pin) &= ~_BV((pin)&0xF)) +# define readPin(pin) ((bool)(PINx_ADDRESS(pin) & _BV((pin)&0xF))) + +# if SOFT_SERIAL_PIN >= D0 && SOFT_SERIAL_PIN <= D3 +# if SOFT_SERIAL_PIN == D0 +# define EIMSK_BIT _BV(INT0) +# define EICRx_BIT (~(_BV(ISC00) | _BV(ISC01))) +# define SERIAL_PIN_INTERRUPT INT0_vect +# elif SOFT_SERIAL_PIN == D1 +# define EIMSK_BIT _BV(INT1) +# define EICRx_BIT (~(_BV(ISC10) | _BV(ISC11))) +# define SERIAL_PIN_INTERRUPT INT1_vect +# elif SOFT_SERIAL_PIN == D2 +# define EIMSK_BIT _BV(INT2) +# define EICRx_BIT (~(_BV(ISC20) | _BV(ISC21))) +# define SERIAL_PIN_INTERRUPT INT2_vect +# elif SOFT_SERIAL_PIN == D3 +# define EIMSK_BIT _BV(INT3) +# define EICRx_BIT (~(_BV(ISC30) | _BV(ISC31))) +# define SERIAL_PIN_INTERRUPT INT3_vect +# endif +# elif SOFT_SERIAL_PIN == E6 +# define EIMSK_BIT _BV(INT6) +# define EICRx_BIT (~(_BV(ISC60) | _BV(ISC61))) +# define SERIAL_PIN_INTERRUPT INT6_vect +# else +# error invalid SOFT_SERIAL_PIN value +# endif + +# else +# error serial.c now support ATmega32U4 only +# endif + +# define ALWAYS_INLINE __attribute__((always_inline)) +# define NO_INLINE __attribute__((noinline)) +# define _delay_sub_us(x) __builtin_avr_delay_cycles(x) + +// parity check +# define ODD_PARITY 1 +# define EVEN_PARITY 0 +# define PARITY EVEN_PARITY + +# ifdef SERIAL_DELAY +// custom setup in config.h +// #define TID_SEND_ADJUST 2 +// #define SERIAL_DELAY 6 // micro sec +// #define READ_WRITE_START_ADJUST 30 // cycles +// #define READ_WRITE_WIDTH_ADJUST 8 // cycles +# else +// ============ Standard setups ============ + +# ifndef SELECT_SOFT_SERIAL_SPEED +# define SELECT_SOFT_SERIAL_SPEED 1 +// 0: about 189kbps (Experimental only) +// 1: about 137kbps (default) +// 2: about 75kbps +// 3: about 39kbps +// 4: about 26kbps +// 5: about 20kbps +# endif + +# if __GNUC__ < 6 +# define TID_SEND_ADJUST 14 +# else +# define TID_SEND_ADJUST 2 +# endif + +# if SELECT_SOFT_SERIAL_SPEED == 0 +// Very High speed +# define SERIAL_DELAY 4 // micro sec +# if __GNUC__ < 6 +# define READ_WRITE_START_ADJUST 33 // cycles +# define READ_WRITE_WIDTH_ADJUST 3 // cycles +# else +# define READ_WRITE_START_ADJUST 34 // cycles +# define READ_WRITE_WIDTH_ADJUST 7 // cycles +# endif +# elif SELECT_SOFT_SERIAL_SPEED == 1 +// High speed +# define SERIAL_DELAY 6 // micro sec +# if __GNUC__ < 6 +# define READ_WRITE_START_ADJUST 30 // cycles +# define READ_WRITE_WIDTH_ADJUST 3 // cycles +# else +# define READ_WRITE_START_ADJUST 33 // cycles +# define READ_WRITE_WIDTH_ADJUST 7 // cycles +# endif +# elif SELECT_SOFT_SERIAL_SPEED == 2 +// Middle speed +# define SERIAL_DELAY 12 // micro sec +# define READ_WRITE_START_ADJUST 30 // cycles +# if __GNUC__ < 6 +# define READ_WRITE_WIDTH_ADJUST 3 // cycles +# else +# define READ_WRITE_WIDTH_ADJUST 7 // cycles +# endif +# elif SELECT_SOFT_SERIAL_SPEED == 3 +// Low speed +# define SERIAL_DELAY 24 // micro sec +# define READ_WRITE_START_ADJUST 30 // cycles +# if __GNUC__ < 6 +# define READ_WRITE_WIDTH_ADJUST 3 // cycles +# else +# define READ_WRITE_WIDTH_ADJUST 7 // cycles +# endif +# elif SELECT_SOFT_SERIAL_SPEED == 4 +// Very Low speed +# define SERIAL_DELAY 36 // micro sec +# define READ_WRITE_START_ADJUST 30 // cycles +# if __GNUC__ < 6 +# define READ_WRITE_WIDTH_ADJUST 3 // cycles +# else +# define READ_WRITE_WIDTH_ADJUST 7 // cycles +# endif +# elif SELECT_SOFT_SERIAL_SPEED == 5 +// Ultra Low speed +# define SERIAL_DELAY 48 // micro sec +# define READ_WRITE_START_ADJUST 30 // cycles +# if __GNUC__ < 6 +# define READ_WRITE_WIDTH_ADJUST 3 // cycles +# else +# define READ_WRITE_WIDTH_ADJUST 7 // cycles +# endif +# else +# error invalid SELECT_SOFT_SERIAL_SPEED value +# endif /* SELECT_SOFT_SERIAL_SPEED */ +# endif /* SERIAL_DELAY */ + +# define SERIAL_DELAY_HALF1 (SERIAL_DELAY / 2) +# define SERIAL_DELAY_HALF2 (SERIAL_DELAY - SERIAL_DELAY / 2) + +# define SLAVE_INT_WIDTH_US 1 +# ifndef SERIAL_USE_MULTI_TRANSACTION +# define SLAVE_INT_RESPONSE_TIME SERIAL_DELAY +# else +# define SLAVE_INT_ACK_WIDTH_UNIT 2 +# define SLAVE_INT_ACK_WIDTH 4 +# endif + +static SSTD_t *Transaction_table = NULL; +static uint8_t Transaction_table_size = 0; + +inline static void serial_delay(void) ALWAYS_INLINE; +inline static void serial_delay(void) { _delay_us(SERIAL_DELAY); } + +inline static void serial_delay_half1(void) ALWAYS_INLINE; +inline static void serial_delay_half1(void) { _delay_us(SERIAL_DELAY_HALF1); } + +inline static void serial_delay_half2(void) ALWAYS_INLINE; +inline static void serial_delay_half2(void) { _delay_us(SERIAL_DELAY_HALF2); } + +inline static void serial_output(void) ALWAYS_INLINE; +inline static void serial_output(void) { setPinOutput(SOFT_SERIAL_PIN); } + +// make the serial pin an input with pull-up resistor +inline static void serial_input_with_pullup(void) ALWAYS_INLINE; +inline static void serial_input_with_pullup(void) { setPinInputHigh(SOFT_SERIAL_PIN); } + +inline static uint8_t serial_read_pin(void) ALWAYS_INLINE; +inline static uint8_t serial_read_pin(void) { return !!readPin(SOFT_SERIAL_PIN); } + +inline static void serial_low(void) ALWAYS_INLINE; +inline static void serial_low(void) { writePinLow(SOFT_SERIAL_PIN); } + +inline static void serial_high(void) ALWAYS_INLINE; +inline static void serial_high(void) { writePinHigh(SOFT_SERIAL_PIN); } + +void soft_serial_initiator_init(SSTD_t *sstd_table, int sstd_table_size) { + Transaction_table = sstd_table; + Transaction_table_size = (uint8_t)sstd_table_size; + serial_output(); + serial_high(); +} + +void soft_serial_target_init(SSTD_t *sstd_table, int sstd_table_size) { + Transaction_table = sstd_table; + Transaction_table_size = (uint8_t)sstd_table_size; + serial_input_with_pullup(); + + // Enable INT0-INT3,INT6 + EIMSK |= EIMSK_BIT; +# if SOFT_SERIAL_PIN == E6 + // Trigger on falling edge of INT6 + EICRB &= EICRx_BIT; +# else + // Trigger on falling edge of INT0-INT3 + EICRA &= EICRx_BIT; +# endif +} + +// Used by the sender to synchronize timing with the reciver. +static void sync_recv(void) NO_INLINE; +static void sync_recv(void) { + for (uint8_t i = 0; i < SERIAL_DELAY * 5 && serial_read_pin(); i++) { + } + // This shouldn't hang if the target disconnects because the + // serial line will float to high if the target does disconnect. + while (!serial_read_pin()) + ; +} + +// Used by the reciver to send a synchronization signal to the sender. +static void sync_send(void) NO_INLINE; +static void sync_send(void) { + serial_low(); + serial_delay(); + serial_high(); +} + +// Reads a byte from the serial line +static uint8_t serial_read_chunk(uint8_t *pterrcount, uint8_t bit) NO_INLINE; +static uint8_t serial_read_chunk(uint8_t *pterrcount, uint8_t bit) { + uint8_t byte, i, p, pb; + + _delay_sub_us(READ_WRITE_START_ADJUST); + for (i = 0, byte = 0, p = PARITY; i < bit; i++) { + serial_delay_half1(); // read the middle of pulses + if (serial_read_pin()) { + byte = (byte << 1) | 1; + p ^= 1; + } else { + byte = (byte << 1) | 0; + p ^= 0; + } + _delay_sub_us(READ_WRITE_WIDTH_ADJUST); + serial_delay_half2(); + } + /* recive parity bit */ + serial_delay_half1(); // read the middle of pulses + pb = serial_read_pin(); + _delay_sub_us(READ_WRITE_WIDTH_ADJUST); + serial_delay_half2(); + + *pterrcount += (p != pb) ? 1 : 0; + + return byte; +} + +// Sends a byte with MSB ordering +void serial_write_chunk(uint8_t data, uint8_t bit) NO_INLINE; +void serial_write_chunk(uint8_t data, uint8_t bit) { + uint8_t b, p; + for (p = PARITY, b = 1 << (bit - 1); b; b >>= 1) { + if (data & b) { + serial_high(); + p ^= 1; + } else { + serial_low(); + p ^= 0; + } + serial_delay(); + } + /* send parity bit */ + if (p & 1) { + serial_high(); + } else { + serial_low(); + } + serial_delay(); + + serial_low(); // sync_send() / senc_recv() need raise edge +} + +static void serial_send_packet(uint8_t *buffer, uint8_t size) NO_INLINE; +static void serial_send_packet(uint8_t *buffer, uint8_t size) { + for (uint8_t i = 0; i < size; ++i) { + uint8_t data; + data = buffer[i]; + sync_send(); + serial_write_chunk(data, 8); + } +} + +static uint8_t serial_recive_packet(uint8_t *buffer, uint8_t size) NO_INLINE; +static uint8_t serial_recive_packet(uint8_t *buffer, uint8_t size) { + uint8_t pecount = 0; + for (uint8_t i = 0; i < size; ++i) { + uint8_t data; + sync_recv(); + data = serial_read_chunk(&pecount, 8); + buffer[i] = data; + } + return pecount == 0; +} + +inline static void change_sender2reciver(void) { + sync_send(); // 0 + serial_delay_half1(); // 1 + serial_low(); // 2 + serial_input_with_pullup(); // 2 + serial_delay_half1(); // 3 +} + +inline static void change_reciver2sender(void) { + sync_recv(); // 0 + serial_delay(); // 1 + serial_low(); // 3 + serial_output(); // 3 + serial_delay_half1(); // 4 +} + +static inline uint8_t nibble_bits_count(uint8_t bits) { + bits = (bits & 0x5) + (bits >> 1 & 0x5); + bits = (bits & 0x3) + (bits >> 2 & 0x3); + return bits; +} + +// interrupt handle to be used by the target device +ISR(SERIAL_PIN_INTERRUPT) { +# ifndef SERIAL_USE_MULTI_TRANSACTION + serial_low(); + serial_output(); + SSTD_t *trans = Transaction_table; +# else + // recive transaction table index + uint8_t tid, bits; + uint8_t pecount = 0; + sync_recv(); + bits = serial_read_chunk(&pecount, 7); + tid = bits >> 3; + bits = (bits & 7) != nibble_bits_count(tid); + if (bits || pecount > 0 || tid > Transaction_table_size) { + return; + } + serial_delay_half1(); + + serial_high(); // response step1 low->high + serial_output(); + _delay_sub_us(SLAVE_INT_ACK_WIDTH_UNIT * SLAVE_INT_ACK_WIDTH); + SSTD_t *trans = &Transaction_table[tid]; + serial_low(); // response step2 ack high->low +# endif + + // target send phase + if (trans->target2initiator_buffer_size > 0) serial_send_packet((uint8_t *)trans->target2initiator_buffer, trans->target2initiator_buffer_size); + // target switch to input + change_sender2reciver(); + + // target recive phase + if (trans->initiator2target_buffer_size > 0) { + if (serial_recive_packet((uint8_t *)trans->initiator2target_buffer, trans->initiator2target_buffer_size)) { + *trans->status = TRANSACTION_ACCEPTED; + } else { + *trans->status = TRANSACTION_DATA_ERROR; + } + } else { + *trans->status = TRANSACTION_ACCEPTED; + } + + sync_recv(); // weit initiator output to high +} + +///////// +// start transaction by initiator +// +// int soft_serial_transaction(int sstd_index) +// +// Returns: +// TRANSACTION_END +// TRANSACTION_NO_RESPONSE +// TRANSACTION_DATA_ERROR +// this code is very time dependent, so we need to disable interrupts +# ifndef SERIAL_USE_MULTI_TRANSACTION +int soft_serial_transaction(void) { + SSTD_t *trans = Transaction_table; +# else +int soft_serial_transaction(int sstd_index) { + if (sstd_index > Transaction_table_size) return TRANSACTION_TYPE_ERROR; + SSTD_t *trans = &Transaction_table[sstd_index]; +# endif + cli(); + + // signal to the target that we want to start a transaction + serial_output(); + serial_low(); + _delay_us(SLAVE_INT_WIDTH_US); + +# ifndef SERIAL_USE_MULTI_TRANSACTION + // wait for the target response + serial_input_with_pullup(); + _delay_us(SLAVE_INT_RESPONSE_TIME); + + // check if the target is present + if (serial_read_pin()) { + // target failed to pull the line low, assume not present + serial_output(); + serial_high(); + *trans->status = TRANSACTION_NO_RESPONSE; + sei(); + return TRANSACTION_NO_RESPONSE; + } + +# else + // send transaction table index + int tid = (sstd_index << 3) | (7 & nibble_bits_count(sstd_index)); + sync_send(); + _delay_sub_us(TID_SEND_ADJUST); + serial_write_chunk(tid, 7); + serial_delay_half1(); + + // wait for the target response (step1 low->high) + serial_input_with_pullup(); + while (!serial_read_pin()) { + _delay_sub_us(2); + } + + // check if the target is present (step2 high->low) + for (int i = 0; serial_read_pin(); i++) { + if (i > SLAVE_INT_ACK_WIDTH + 1) { + // slave failed to pull the line low, assume not present + serial_output(); + serial_high(); + *trans->status = TRANSACTION_NO_RESPONSE; + sei(); + return TRANSACTION_NO_RESPONSE; + } + _delay_sub_us(SLAVE_INT_ACK_WIDTH_UNIT); + } +# endif + + // initiator recive phase + // if the target is present syncronize with it + if (trans->target2initiator_buffer_size > 0) { + if (!serial_recive_packet((uint8_t *)trans->target2initiator_buffer, trans->target2initiator_buffer_size)) { + serial_output(); + serial_high(); + *trans->status = TRANSACTION_DATA_ERROR; + sei(); + return TRANSACTION_DATA_ERROR; + } + } + + // initiator switch to output + change_reciver2sender(); + + // initiator send phase + if (trans->initiator2target_buffer_size > 0) { + serial_send_packet((uint8_t *)trans->initiator2target_buffer, trans->initiator2target_buffer_size); + } + + // always, release the line when not in use + sync_send(); + + *trans->status = TRANSACTION_END; + sei(); + return TRANSACTION_END; +} + +# ifdef SERIAL_USE_MULTI_TRANSACTION +int soft_serial_get_and_clean_status(int sstd_index) { + SSTD_t *trans = &Transaction_table[sstd_index]; + cli(); + int retval = *trans->status; + *trans->status = 0; + ; + sei(); + return retval; +} +# endif + +#endif + +// Helix serial.c history +// 2018-1-29 fork from let's split and add PD2, modify sync_recv() (#2308, bceffdefc) +// 2018-6-28 bug fix master to slave comm and speed up (#3255, 1038bbef4) +// (adjusted with avr-gcc 4.9.2) +// 2018-7-13 remove USE_SERIAL_PD2 macro (#3374, f30d6dd78) +// (adjusted with avr-gcc 4.9.2) +// 2018-8-11 add support multi-type transaction (#3608, feb5e4aae) +// (adjusted with avr-gcc 4.9.2) +// 2018-10-21 fix serial and RGB animation conflict (#4191, 4665e4fff) +// (adjusted with avr-gcc 7.3.0) +// 2018-10-28 re-adjust compiler depend value of delay (#4269, 8517f8a66) +// (adjusted with avr-gcc 5.4.0, 7.3.0) +// 2018-12-17 copy to TOP/quantum/split_common/ and remove backward compatibility code (#4669) |