Firmware/Marlin/MarlinSerial.cpp
2018-06-08 19:53:39 -05:00

598 lines
17 KiB
C++

/**
* Marlin 3D Printer Firmware
* Copyright (C) 2016 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
*
* Based on Sprinter and grbl.
* Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
/**
* MarlinSerial.cpp - Hardware serial library for Wiring
* Copyright (c) 2006 Nicholas Zambetti. All right reserved.
*
* Modified 23 November 2006 by David A. Mellis
* Modified 28 September 2010 by Mark Sproul
* Modified 14 February 2016 by Andreas Hardtung (added tx buffer)
* Modified 01 October 2017 by Eduardo José Tagle (added XON/XOFF)
*/
// Disable HardwareSerial.cpp to support chips without a UART (Attiny, etc.)
#include "MarlinConfig.h"
#if USE_MARLINSERIAL && (defined(UBRRH) || defined(UBRR0H) || defined(UBRR1H) || defined(UBRR2H) || defined(UBRR3H))
#include "MarlinSerial.h"
#include "Marlin.h"
struct ring_buffer_r {
unsigned char buffer[RX_BUFFER_SIZE];
volatile ring_buffer_pos_t head, tail;
};
#if TX_BUFFER_SIZE > 0
struct ring_buffer_t {
unsigned char buffer[TX_BUFFER_SIZE];
volatile uint8_t head, tail;
};
#endif
#if UART_PRESENT(SERIAL_PORT)
ring_buffer_r rx_buffer = { { 0 }, 0, 0 };
#if TX_BUFFER_SIZE > 0
ring_buffer_t tx_buffer = { { 0 }, 0, 0 };
static bool _written;
#endif
#endif
#if ENABLED(SERIAL_XON_XOFF)
constexpr uint8_t XON_XOFF_CHAR_SENT = 0x80; // XON / XOFF Character was sent
constexpr uint8_t XON_XOFF_CHAR_MASK = 0x1F; // XON / XOFF character to send
// XON / XOFF character definitions
constexpr uint8_t XON_CHAR = 17;
constexpr uint8_t XOFF_CHAR = 19;
uint8_t xon_xoff_state = XON_XOFF_CHAR_SENT | XON_CHAR;
#endif
#if ENABLED(SERIAL_STATS_DROPPED_RX)
uint8_t rx_dropped_bytes = 0;
#endif
#if ENABLED(SERIAL_STATS_MAX_RX_QUEUED)
ring_buffer_pos_t rx_max_enqueued = 0;
#endif
// A SW memory barrier, to ensure GCC does not overoptimize loops
#define sw_barrier() asm volatile("": : :"memory");
#if ENABLED(EMERGENCY_PARSER)
#include "emergency_parser.h"
#endif
// (called with RX interrupts disabled)
FORCE_INLINE void store_rxd_char() {
const ring_buffer_pos_t h = rx_buffer.head,
i = (ring_buffer_pos_t)(h + 1) & (ring_buffer_pos_t)(RX_BUFFER_SIZE - 1);
// If the character is to be stored at the index just before the tail
// (such that the head would advance to the current tail), the buffer is
// critical, so don't write the character or advance the head.
const char c = M_UDRx;
if (i != rx_buffer.tail) {
rx_buffer.buffer[h] = c;
rx_buffer.head = i;
}
else {
#if ENABLED(SERIAL_STATS_DROPPED_RX)
if (!++rx_dropped_bytes) ++rx_dropped_bytes;
#endif
}
#if ENABLED(SERIAL_STATS_MAX_RX_QUEUED)
// calculate count of bytes stored into the RX buffer
ring_buffer_pos_t rx_count = (ring_buffer_pos_t)(rx_buffer.head - rx_buffer.tail) & (ring_buffer_pos_t)(RX_BUFFER_SIZE - 1);
// Keep track of the maximum count of enqueued bytes
NOLESS(rx_max_enqueued, rx_count);
#endif
#if ENABLED(SERIAL_XON_XOFF)
// for high speed transfers, we can use XON/XOFF protocol to do
// software handshake and avoid overruns.
if ((xon_xoff_state & XON_XOFF_CHAR_MASK) == XON_CHAR) {
// calculate count of bytes stored into the RX buffer
ring_buffer_pos_t rx_count = (ring_buffer_pos_t)(rx_buffer.head - rx_buffer.tail) & (ring_buffer_pos_t)(RX_BUFFER_SIZE - 1);
// if we are above 12.5% of RX buffer capacity, send XOFF before
// we run out of RX buffer space .. We need 325 bytes @ 250kbits/s to
// let the host react and stop sending bytes. This translates to 13mS
// propagation time.
if (rx_count >= (RX_BUFFER_SIZE) / 8) {
// If TX interrupts are disabled and data register is empty,
// just write the byte to the data register and be done. This
// shortcut helps significantly improve the effective datarate
// at high (>500kbit/s) bitrates, where interrupt overhead
// becomes a slowdown.
if (!TEST(M_UCSRxB, M_UDRIEx) && TEST(M_UCSRxA, M_UDREx)) {
// Send an XOFF character
M_UDRx = XOFF_CHAR;
// clear the TXC bit -- "can be cleared by writing a one to its bit
// location". This makes sure flush() won't return until the bytes
// actually got written
SBI(M_UCSRxA, M_TXCx);
// And remember it was sent
xon_xoff_state = XOFF_CHAR | XON_XOFF_CHAR_SENT;
}
else {
// TX interrupts disabled, but buffer still not empty ... or
// TX interrupts enabled. Reenable TX ints and schedule XOFF
// character to be sent
#if TX_BUFFER_SIZE > 0
SBI(M_UCSRxB, M_UDRIEx);
xon_xoff_state = XOFF_CHAR;
#else
// We are not using TX interrupts, we will have to send this manually
while (!TEST(M_UCSRxA, M_UDREx)) sw_barrier();
M_UDRx = XOFF_CHAR;
// clear the TXC bit -- "can be cleared by writing a one to its bit
// location". This makes sure flush() won't return until the bytes
// actually got written
SBI(M_UCSRxA, M_TXCx);
// And remember we already sent it
xon_xoff_state = XOFF_CHAR | XON_XOFF_CHAR_SENT;
#endif
}
}
}
#endif // SERIAL_XON_XOFF
#if ENABLED(EMERGENCY_PARSER)
emergency_parser.update(c);
#endif
}
#if TX_BUFFER_SIZE > 0
// (called with TX irqs disabled)
FORCE_INLINE void _tx_udr_empty_irq(void) {
// If interrupts are enabled, there must be more data in the output
// buffer.
#if ENABLED(SERIAL_XON_XOFF)
// Do a priority insertion of an XON/XOFF char, if needed.
const uint8_t state = xon_xoff_state;
if (!(state & XON_XOFF_CHAR_SENT)) {
M_UDRx = state & XON_XOFF_CHAR_MASK;
xon_xoff_state = state | XON_XOFF_CHAR_SENT;
}
else
#endif
{ // Send the next byte
const uint8_t t = tx_buffer.tail, c = tx_buffer.buffer[t];
tx_buffer.tail = (t + 1) & (TX_BUFFER_SIZE - 1);
M_UDRx = c;
}
// clear the TXC bit -- "can be cleared by writing a one to its bit
// location". This makes sure flush() won't return until the bytes
// actually got written
SBI(M_UCSRxA, M_TXCx);
// Disable interrupts if the buffer is empty
if (tx_buffer.head == tx_buffer.tail)
CBI(M_UCSRxB, M_UDRIEx);
}
#ifdef M_USARTx_UDRE_vect
ISR(M_USARTx_UDRE_vect) { _tx_udr_empty_irq(); }
#endif
#endif // TX_BUFFER_SIZE
#ifdef M_USARTx_RX_vect
ISR(M_USARTx_RX_vect) { store_rxd_char(); }
#endif
// Public Methods
void MarlinSerial::begin(const long baud) {
uint16_t baud_setting;
bool useU2X = true;
#if F_CPU == 16000000UL && SERIAL_PORT == 0
// Hard-coded exception for compatibility with the bootloader shipped
// with the Duemilanove and previous boards, and the firmware on the
// 8U2 on the Uno and Mega 2560.
if (baud == 57600) useU2X = false;
#endif
if (useU2X) {
M_UCSRxA = _BV(M_U2Xx);
baud_setting = (F_CPU / 4 / baud - 1) / 2;
}
else {
M_UCSRxA = 0;
baud_setting = (F_CPU / 8 / baud - 1) / 2;
}
// assign the baud_setting, a.k.a. ubbr (USART Baud Rate Register)
M_UBRRxH = baud_setting >> 8;
M_UBRRxL = baud_setting;
SBI(M_UCSRxB, M_RXENx);
SBI(M_UCSRxB, M_TXENx);
SBI(M_UCSRxB, M_RXCIEx);
#if TX_BUFFER_SIZE > 0
CBI(M_UCSRxB, M_UDRIEx);
_written = false;
#endif
}
void MarlinSerial::end() {
CBI(M_UCSRxB, M_RXENx);
CBI(M_UCSRxB, M_TXENx);
CBI(M_UCSRxB, M_RXCIEx);
CBI(M_UCSRxB, M_UDRIEx);
}
int MarlinSerial::peek(void) {
#if RX_BUFFER_SIZE > 256
// Disable RX interrupts, but only if non atomic reads
const bool isr_enabled = TEST(M_UCSRxB, M_RXCIEx);
CBI(M_UCSRxB, M_RXCIEx);
#endif
const int v = rx_buffer.head == rx_buffer.tail ? -1 : rx_buffer.buffer[rx_buffer.tail];
#if RX_BUFFER_SIZE > 256
// Reenable RX interrupts if they were enabled
if (isr_enabled) SBI(M_UCSRxB, M_RXCIEx);
#endif
return v;
}
int MarlinSerial::read(void) {
int v;
#if RX_BUFFER_SIZE > 256
// Disable RX interrupts to ensure atomic reads
const bool isr_enabled = TEST(M_UCSRxB, M_RXCIEx);
CBI(M_UCSRxB, M_RXCIEx);
#endif
const ring_buffer_pos_t h = rx_buffer.head;
#if RX_BUFFER_SIZE > 256
// End critical section
if (isr_enabled) SBI(M_UCSRxB, M_RXCIEx);
#endif
ring_buffer_pos_t t = rx_buffer.tail;
if (h == t)
v = -1;
else {
v = rx_buffer.buffer[t];
t = (ring_buffer_pos_t)(t + 1) & (RX_BUFFER_SIZE - 1);
#if RX_BUFFER_SIZE > 256
// Disable RX interrupts to ensure atomic write to tail, so
// the RX isr can't read partially updated values
const bool isr_enabled = TEST(M_UCSRxB, M_RXCIEx);
CBI(M_UCSRxB, M_RXCIEx);
#endif
// Advance tail
rx_buffer.tail = t;
#if RX_BUFFER_SIZE > 256
// End critical section
if (isr_enabled) SBI(M_UCSRxB, M_RXCIEx);
#endif
#if ENABLED(SERIAL_XON_XOFF)
if ((xon_xoff_state & XON_XOFF_CHAR_MASK) == XOFF_CHAR) {
// Get count of bytes in the RX buffer
ring_buffer_pos_t rx_count = (ring_buffer_pos_t)(h - t) & (ring_buffer_pos_t)(RX_BUFFER_SIZE - 1);
// When below 10% of RX buffer capacity, send XON before
// running out of RX buffer bytes
if (rx_count < (RX_BUFFER_SIZE) / 10) {
xon_xoff_state = XON_CHAR | XON_XOFF_CHAR_SENT;
write(XON_CHAR);
return v;
}
}
#endif
}
return v;
}
ring_buffer_pos_t MarlinSerial::available(void) {
#if RX_BUFFER_SIZE > 256
const bool isr_enabled = TEST(M_UCSRxB, M_RXCIEx);
CBI(M_UCSRxB, M_RXCIEx);
#endif
const ring_buffer_pos_t h = rx_buffer.head, t = rx_buffer.tail;
#if RX_BUFFER_SIZE > 256
if (isr_enabled) SBI(M_UCSRxB, M_RXCIEx);
#endif
return (ring_buffer_pos_t)(RX_BUFFER_SIZE + h - t) & (RX_BUFFER_SIZE - 1);
}
void MarlinSerial::flush(void) {
#if RX_BUFFER_SIZE > 256
const bool isr_enabled = TEST(M_UCSRxB, M_RXCIEx);
CBI(M_UCSRxB, M_RXCIEx);
#endif
rx_buffer.tail = rx_buffer.head;
#if RX_BUFFER_SIZE > 256
if (isr_enabled) SBI(M_UCSRxB, M_RXCIEx);
#endif
#if ENABLED(SERIAL_XON_XOFF)
if ((xon_xoff_state & XON_XOFF_CHAR_MASK) == XOFF_CHAR) {
xon_xoff_state = XON_CHAR | XON_XOFF_CHAR_SENT;
write(XON_CHAR);
}
#endif
}
#if TX_BUFFER_SIZE > 0
void MarlinSerial::write(const uint8_t c) {
_written = true;
// If the TX interrupts are disabled and the data register
// is empty, just write the byte to the data register and
// be done. This shortcut helps significantly improve the
// effective datarate at high (>500kbit/s) bitrates, where
// interrupt overhead becomes a slowdown.
if (!TEST(M_UCSRxB, M_UDRIEx) && TEST(M_UCSRxA, M_UDREx)) {
M_UDRx = c;
// clear the TXC bit -- "can be cleared by writing a one to its bit
// location". This makes sure flush() won't return until the bytes
// actually got written
SBI(M_UCSRxA, M_TXCx);
return;
}
const uint8_t i = (tx_buffer.head + 1) & (TX_BUFFER_SIZE - 1);
// If the output buffer is full, there's nothing for it other than to
// wait for the interrupt handler to empty it a bit
while (i == tx_buffer.tail) {
if (!ISRS_ENABLED()) {
// Interrupts are disabled, so we'll have to poll the data
// register empty flag ourselves. If it is set, pretend an
// interrupt has happened and call the handler to free up
// space for us.
if (TEST(M_UCSRxA, M_UDREx))
_tx_udr_empty_irq();
}
// (else , the interrupt handler will free up space for us)
// Make sure compiler rereads tx_buffer.tail
sw_barrier();
}
// Store new char. head is always safe to move
tx_buffer.buffer[tx_buffer.head] = c;
tx_buffer.head = i;
// Enable TX isr
SBI(M_UCSRxB, M_UDRIEx);
return;
}
void MarlinSerial::flushTX(void) {
// TX
// If we have never written a byte, no need to flush. This special
// case is needed since there is no way to force the TXC (transmit
// complete) bit to 1 during initialization
if (!_written)
return;
while (TEST(M_UCSRxB, M_UDRIEx) || !TEST(M_UCSRxA, M_TXCx)) {
if (!ISRS_ENABLED()) {
// Interrupts are globally disabled, but the DR empty
// interrupt should be enabled, so poll the DR empty flag to
// prevent deadlock
if (TEST(M_UCSRxA, M_UDREx))
_tx_udr_empty_irq();
}
sw_barrier();
}
// If we get here, nothing is queued anymore (DRIE is disabled) and
// the hardware finished transmission (TXC is set).
}
#else // TX_BUFFER_SIZE == 0
void MarlinSerial::write(const uint8_t c) {
while (!TEST(M_UCSRxA, M_UDREx)) sw_barrier();
M_UDRx = c;
}
#endif // TX_BUFFER_SIZE == 0
/**
* Imports from print.h
*/
void MarlinSerial::print(char c, int base) {
print((long)c, base);
}
void MarlinSerial::print(unsigned char b, int base) {
print((unsigned long)b, base);
}
void MarlinSerial::print(int n, int base) {
print((long)n, base);
}
void MarlinSerial::print(unsigned int n, int base) {
print((unsigned long)n, base);
}
void MarlinSerial::print(long n, int base) {
if (base == 0)
write(n);
else if (base == 10) {
if (n < 0) {
print('-');
n = -n;
}
printNumber(n, 10);
}
else
printNumber(n, base);
}
void MarlinSerial::print(unsigned long n, int base) {
if (base == 0) write(n);
else printNumber(n, base);
}
void MarlinSerial::print(double n, int digits) {
printFloat(n, digits);
}
void MarlinSerial::println(void) {
print('\r');
print('\n');
}
void MarlinSerial::println(const String& s) {
print(s);
println();
}
void MarlinSerial::println(const char c[]) {
print(c);
println();
}
void MarlinSerial::println(char c, int base) {
print(c, base);
println();
}
void MarlinSerial::println(unsigned char b, int base) {
print(b, base);
println();
}
void MarlinSerial::println(int n, int base) {
print(n, base);
println();
}
void MarlinSerial::println(unsigned int n, int base) {
print(n, base);
println();
}
void MarlinSerial::println(long n, int base) {
print(n, base);
println();
}
void MarlinSerial::println(unsigned long n, int base) {
print(n, base);
println();
}
void MarlinSerial::println(double n, int digits) {
print(n, digits);
println();
}
// Private Methods
void MarlinSerial::printNumber(unsigned long n, uint8_t base) {
if (n) {
unsigned char buf[8 * sizeof(long)]; // Enough space for base 2
int8_t i = 0;
while (n) {
buf[i++] = n % base;
n /= base;
}
while (i--)
print((char)(buf[i] + (buf[i] < 10 ? '0' : 'A' - 10)));
}
else
print('0');
}
void MarlinSerial::printFloat(double number, uint8_t digits) {
// Handle negative numbers
if (number < 0.0) {
print('-');
number = -number;
}
// Round correctly so that print(1.999, 2) prints as "2.00"
double rounding = 0.5;
for (uint8_t i = 0; i < digits; ++i)
rounding *= 0.1;
number += rounding;
// Extract the integer part of the number and print it
unsigned long int_part = (unsigned long)number;
double remainder = number - (double)int_part;
print(int_part);
// Print the decimal point, but only if there are digits beyond
if (digits) {
print('.');
// Extract digits from the remainder one at a time
while (digits--) {
remainder *= 10.0;
int toPrint = int(remainder);
print(toPrint);
remainder -= toPrint;
}
}
}
// Preinstantiate
MarlinSerial customizedSerial;
#endif // USE_MARLINSERIAL && (UBRRH || UBRR0H || UBRR1H || UBRR2H || UBRR3H)
// For AT90USB targets use the UART for BT interfacing
#if !USE_MARLINSERIAL && ENABLED(BLUETOOTH)
HardwareSerial bluetoothSerial;
#endif