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-rw-r--r--platforms/avr/drivers/serial.c529
1 files changed, 529 insertions, 0 deletions
diff --git a/platforms/avr/drivers/serial.c b/platforms/avr/drivers/serial.c
new file mode 100644
index 0000000000..9a7345a53d
--- /dev/null
+++ b/platforms/avr/drivers/serial.c
@@ -0,0 +1,529 @@
+/*
+ * 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
+
+# if !(defined(__AVR_AT90USB646__) || defined(__AVR_AT90USB647__) || defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB1287__) || defined(__AVR_AT90USB162__) || defined(__AVR_ATmega16U2__) || defined(__AVR_ATmega32U2__) || defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__))
+# error serial.c is not supported for the currently selected MCU
+# endif
+// if using ATmega32U4/2, AT90USBxxx I2C, can not use PD0 and PD1 in soft serial.
+# if defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__) || defined(__AVR_AT90USB646__) || defined(__AVR_AT90USB647__) || defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB1287__)
+# if defined(USE_AVR_I2C) && (SOFT_SERIAL_PIN == D0 || SOFT_SERIAL_PIN == D1)
+# error Using I2C, so can not use PD0, PD1
+# endif
+# endif
+// PD0..PD3, common config
+# if SOFT_SERIAL_PIN == D0
+# define EIMSK_BIT _BV(INT0)
+# define EICRx_BIT (~(_BV(ISC00) | _BV(ISC01)))
+# define SERIAL_PIN_INTERRUPT INT0_vect
+# define EICRx EICRA
+# elif SOFT_SERIAL_PIN == D1
+# define EIMSK_BIT _BV(INT1)
+# define EICRx_BIT (~(_BV(ISC10) | _BV(ISC11)))
+# define SERIAL_PIN_INTERRUPT INT1_vect
+# define EICRx EICRA
+# elif SOFT_SERIAL_PIN == D2
+# define EIMSK_BIT _BV(INT2)
+# define EICRx_BIT (~(_BV(ISC20) | _BV(ISC21)))
+# define SERIAL_PIN_INTERRUPT INT2_vect
+# define EICRx EICRA
+# elif SOFT_SERIAL_PIN == D3
+# define EIMSK_BIT _BV(INT3)
+# define EICRx_BIT (~(_BV(ISC30) | _BV(ISC31)))
+# define SERIAL_PIN_INTERRUPT INT3_vect
+# define EICRx EICRA
+# endif
+
+// ATmegaxxU2/AT90USB162 specific config
+# if defined(__AVR_ATmega16U2__) || defined(__AVR_ATmega32U2__) || defined(__AVR_AT90USB162__)
+// PD4(INT5), PD6(INT6), PD7(INT7), PC7(INT4)
+# if SOFT_SERIAL_PIN == D4
+# define EIMSK_BIT _BV(INT5)
+# define EICRx_BIT (~(_BV(ISC50) | _BV(ISC51)))
+# define SERIAL_PIN_INTERRUPT INT5_vect
+# define EICRx EICRB
+# elif SOFT_SERIAL_PIN == D6
+# define EIMSK_BIT _BV(INT6)
+# define EICRx_BIT (~(_BV(ISC60) | _BV(ISC61)))
+# define SERIAL_PIN_INTERRUPT INT6_vect
+# define EICRx EICRB
+# elif SOFT_SERIAL_PIN == D7
+# define EIMSK_BIT _BV(INT7)
+# define EICRx_BIT (~(_BV(ISC70) | _BV(ISC71)))
+# define SERIAL_PIN_INTERRUPT INT7_vect
+# define EICRx EICRB
+# elif SOFT_SERIAL_PIN == C7
+# define EIMSK_BIT _BV(INT4)
+# define EICRx_BIT (~(_BV(ISC40) | _BV(ISC41)))
+# define SERIAL_PIN_INTERRUPT INT4_vect
+# define EICRx EICRB
+# endif
+# endif
+
+// ATmegaxxU4 specific config
+# if defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__)
+// PE6(INT6)
+# if SOFT_SERIAL_PIN == E6
+# define EIMSK_BIT _BV(INT6)
+# define EICRx_BIT (~(_BV(ISC60) | _BV(ISC61)))
+# define SERIAL_PIN_INTERRUPT INT6_vect
+# define EICRx EICRB
+# endif
+# endif
+
+// AT90USBxxx specific config
+# if defined(__AVR_AT90USB646__) || defined(__AVR_AT90USB647__) || defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB1287__)
+// PE4..PE7(INT4..INT7)
+# if SOFT_SERIAL_PIN == E4
+# define EIMSK_BIT _BV(INT4)
+# define EICRx_BIT (~(_BV(ISC40) | _BV(ISC41)))
+# define SERIAL_PIN_INTERRUPT INT4_vect
+# define EICRx EICRB
+# elif SOFT_SERIAL_PIN == E5
+# define EIMSK_BIT _BV(INT5)
+# define EICRx_BIT (~(_BV(ISC50) | _BV(ISC51)))
+# define SERIAL_PIN_INTERRUPT INT5_vect
+# define EICRx EICRB
+# elif SOFT_SERIAL_PIN == E6
+# define EIMSK_BIT _BV(INT6)
+# define EICRx_BIT (~(_BV(ISC60) | _BV(ISC61)))
+# define SERIAL_PIN_INTERRUPT INT6_vect
+# define EICRx EICRB
+# elif SOFT_SERIAL_PIN == E7
+# define EIMSK_BIT _BV(INT7)
+# define EICRx_BIT (~(_BV(ISC70) | _BV(ISC71)))
+# define SERIAL_PIN_INTERRUPT INT7_vect
+# define EICRx EICRB
+# endif
+# endif
+
+# ifndef SERIAL_PIN_INTERRUPT
+# error invalid SOFT_SERIAL_PIN value
+# 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)))
+
+# 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
+# define SLAVE_INT_ACK_WIDTH_UNIT 2
+# define SLAVE_INT_ACK_WIDTH 4
+
+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(void) {
+ serial_output();
+ serial_high();
+}
+
+void soft_serial_target_init(void) {
+ serial_input_with_pullup();
+
+ // Enable INT0-INT7
+ EIMSK |= EIMSK_BIT;
+ EICRx &= EICRx_BIT;
+}
+
+// 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) {
+ // recive transaction table index
+ uint8_t tid, bits;
+ uint8_t pecount = 0;
+ sync_recv();
+ bits = serial_read_chunk(&pecount, 8);
+ tid = bits >> 3;
+ bits = (bits & 7) != (nibble_bits_count(tid) & 7);
+ if (bits || pecount > 0 || tid > NUM_TOTAL_TRANSACTIONS) {
+ return;
+ }
+ serial_delay_half1();
+
+ serial_high(); // response step1 low->high
+ serial_output();
+ _delay_sub_us(SLAVE_INT_ACK_WIDTH_UNIT * SLAVE_INT_ACK_WIDTH);
+ split_transaction_desc_t *trans = &split_transaction_table[tid];
+ serial_low(); // response step2 ack high->low
+
+ // If the transaction has a callback, we can execute it now
+ if (trans->slave_callback) {
+ trans->slave_callback(trans->initiator2target_buffer_size, split_trans_initiator2target_buffer(trans), trans->target2initiator_buffer_size, split_trans_target2initiator_buffer(trans));
+ }
+
+ // target send phase
+ if (trans->target2initiator_buffer_size > 0) serial_send_packet((uint8_t *)split_trans_target2initiator_buffer(trans), 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 *)split_trans_initiator2target_buffer(trans), 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
+int soft_serial_transaction(int sstd_index) {
+ if (sstd_index > NUM_TOTAL_TRANSACTIONS) return TRANSACTION_TYPE_ERROR;
+ split_transaction_desc_t *trans = &split_transaction_table[sstd_index];
+
+ if (!trans->status) return TRANSACTION_TYPE_ERROR; // not registered
+
+ cli();
+
+ // signal to the target that we want to start a transaction
+ serial_output();
+ serial_low();
+ _delay_us(SLAVE_INT_WIDTH_US);
+
+ // send transaction table index
+ int tid = (sstd_index << 3) | (7 & nibble_bits_count(sstd_index));
+ sync_send();
+ _delay_sub_us(TID_SEND_ADJUST);
+ serial_write_chunk(tid, 8);
+ serial_delay_half1();
+
+ // wait for the target response (step1 low->high)
+ serial_input_with_pullup();
+ while (!serial_read_pin()) {
+ _delay_sub_us(2);
+ }
+
+ // check if the target is present (step2 high->low)
+ for (int i = 0; serial_read_pin(); i++) {
+ if (i > SLAVE_INT_ACK_WIDTH + 1) {
+ // slave failed to pull the line low, assume not present
+ serial_output();
+ serial_high();
+ *trans->status = TRANSACTION_NO_RESPONSE;
+ sei();
+ return TRANSACTION_NO_RESPONSE;
+ }
+ _delay_sub_us(SLAVE_INT_ACK_WIDTH_UNIT);
+ }
+
+ // initiator recive phase
+ // if the target is present syncronize with it
+ if (trans->target2initiator_buffer_size > 0) {
+ if (!serial_recive_packet((uint8_t *)split_trans_target2initiator_buffer(trans), trans->target2initiator_buffer_size)) {
+ serial_output();
+ serial_high();
+ *trans->status = TRANSACTION_DATA_ERROR;
+ sei();
+ return TRANSACTION_DATA_ERROR;
+ }
+ }
+
+ // initiator switch to output
+ change_reciver2sender();
+
+ // initiator send phase
+ if (trans->initiator2target_buffer_size > 0) {
+ serial_send_packet((uint8_t *)split_trans_initiator2target_buffer(trans), trans->initiator2target_buffer_size);
+ }
+
+ // always, release the line when not in use
+ sync_send();
+
+ *trans->status = TRANSACTION_END;
+ sei();
+ return TRANSACTION_END;
+}
+
+int soft_serial_get_and_clean_status(int sstd_index) {
+ split_transaction_desc_t *trans = &split_transaction_table[sstd_index];
+ cli();
+ int retval = *trans->status;
+ *trans->status = 0;
+ ;
+ sei();
+ return retval;
+}
+#endif
+
+// Helix serial.c history
+// 2018-1-29 fork from let's split and add PD2, modify sync_recv() (#2308, bceffdefc)
+// 2018-6-28 bug fix master to slave comm and speed up (#3255, 1038bbef4)
+// (adjusted with avr-gcc 4.9.2)
+// 2018-7-13 remove USE_SERIAL_PD2 macro (#3374, f30d6dd78)
+// (adjusted with avr-gcc 4.9.2)
+// 2018-8-11 add support multi-type transaction (#3608, feb5e4aae)
+// (adjusted with avr-gcc 4.9.2)
+// 2018-10-21 fix serial and RGB animation conflict (#4191, 4665e4fff)
+// (adjusted with avr-gcc 7.3.0)
+// 2018-10-28 re-adjust compiler depend value of delay (#4269, 8517f8a66)
+// (adjusted with avr-gcc 5.4.0, 7.3.0)
+// 2018-12-17 copy to TOP/quantum/split_common/ and remove backward compatibility code (#4669)