/* Teensyduino Core Library * http://www.pjrc.com/teensy/ * Copyright (c) 2019 PJRC.COM, LLC. * * Permission is hereby granted, free of charge, to any person obtaining * a copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * 1. The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * 2. If the Software is incorporated into a build system that allows * selection among a list of target devices, then similar target * devices manufactured by PJRC.COM must be included in the list of * target devices and selectable in the same manner. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ #include "HardwareSerial.h" #include "core_pins.h" #include "Arduino.h" //#include "debug/printf.h" /*typedef struct { const uint32_t VERID; const uint32_t PARAM; volatile uint32_t GLOBAL; volatile uint32_t PINCFG; volatile uint32_t BAUD; volatile uint32_t STAT; volatile uint32_t CTRL; volatile uint32_t DATA; volatile uint32_t MATCH; volatile uint32_t MODIR; volatile uint32_t FIFO; volatile uint32_t WATER; } IMXRT_LPUART_t; */ //. From Onewire utility files #define PIN_TO_BASEREG(pin) (portOutputRegister(pin)) #define PIN_TO_BITMASK(pin) (digitalPinToBitMask(pin)) #define IO_REG_TYPE uint32_t #define IO_REG_BASE_ATTR #define IO_REG_MASK_ATTR #define DIRECT_READ(base, mask) ((*((base)+2) & (mask)) ? 1 : 0) #define DIRECT_MODE_INPUT(base, mask) (*((base)+1) &= ~(mask)) #define DIRECT_MODE_OUTPUT(base, mask) (*((base)+1) |= (mask)) #define DIRECT_WRITE_LOW(base, mask) (*((base)+34) = (mask)) #define DIRECT_WRITE_HIGH(base, mask) (*((base)+33) = (mask)) #define UART_CLOCK 24000000 SerialEventCheckingFunctionPointer HardwareSerial::serial_event_handler_checks[8] = {nullptr, nullptr, nullptr, nullptr, nullptr, nullptr, nullptr, nullptr}; uint8_t HardwareSerial::serial_event_handlers_active = 0; #define CTRL_ENABLE (LPUART_CTRL_TE | LPUART_CTRL_RE | LPUART_CTRL_RIE | LPUART_CTRL_ILIE) #define CTRL_TX_ACTIVE (CTRL_ENABLE | LPUART_CTRL_TIE) #define CTRL_TX_COMPLETING (CTRL_ENABLE | LPUART_CTRL_TCIE) #define CTRL_TX_INACTIVE CTRL_ENABLE // Copied from T3.x - probably should move to other location. int nvic_execution_priority(void) { uint32_t priority=256; uint32_t primask, faultmask, basepri, ipsr; // full algorithm in ARM DDI0403D, page B1-639 // this isn't quite complete, but hopefully good enough __asm__ volatile("mrs %0, faultmask\n" : "=r" (faultmask)::); if (faultmask) return -1; __asm__ volatile("mrs %0, primask\n" : "=r" (primask)::); if (primask) return 0; __asm__ volatile("mrs %0, ipsr\n" : "=r" (ipsr)::); if (ipsr) { if (ipsr < 16) priority = 0; // could be non-zero else priority = NVIC_GET_PRIORITY(ipsr - 16); } __asm__ volatile("mrs %0, basepri\n" : "=r" (basepri)::); if (basepri > 0 && basepri < priority) priority = basepri; return priority; } void HardwareSerial::begin(uint32_t baud, uint16_t format) { //printf("HardwareSerial begin\n"); float base = (float)UART_CLOCK / (float)baud; float besterr = 1e20; int bestdiv = 1; int bestosr = 4; for (int osr=4; osr <= 32; osr++) { float div = base / (float)osr; int divint = (int)(div + 0.5f); if (divint < 1) divint = 1; else if (divint > 8191) divint = 8191; float err = ((float)divint - div) / div; if (err < 0.0f) err = -err; if (err <= besterr) { besterr = err; bestdiv = divint; bestosr = osr; } } //printf(" baud %d: osr=%d, div=%d\n", baud, bestosr, bestdiv); rx_buffer_head_ = 0; rx_buffer_tail_ = 0; tx_buffer_head_ = 0; tx_buffer_tail_ = 0; rts_low_watermark_ = rx_buffer_total_size_ - hardware->rts_low_watermark; rts_high_watermark_ = rx_buffer_total_size_ - hardware->rts_high_watermark; transmitting_ = 0; hardware->ccm_register |= hardware->ccm_value; uint32_t fastio = IOMUXC_PAD_SRE | IOMUXC_PAD_DSE(3) | IOMUXC_PAD_SPEED(3); *(portControlRegister(hardware->rx_pin)) = fastio; *(portControlRegister(hardware->tx_pin)) = fastio; *(portConfigRegister(hardware->rx_pin)) = hardware->rx_mux_val; *(portConfigRegister(hardware->tx_pin)) = hardware->tx_mux_val; //hardware->rx_mux_register = hardware->rx_mux_val; //hardware->tx_mux_register = hardware->tx_mux_val; hardware->rx_select_input_register = hardware->rx_select_val; port->BAUD = LPUART_BAUD_OSR(bestosr - 1) | LPUART_BAUD_SBR(bestdiv); port->PINCFG = 0; // Enable the transmitter, receiver and enable receiver interrupt attachInterruptVector(hardware->irq, hardware->irq_handler); NVIC_SET_PRIORITY(hardware->irq, hardware->irq_priority); // maybe should put into hardware... NVIC_ENABLE_IRQ(hardware->irq); uint16_t tx_fifo_size = (((port->FIFO >> 4) & 0x7) << 2); uint8_t tx_water = (tx_fifo_size < 16) ? tx_fifo_size >> 1 : 7; uint16_t rx_fifo_size = (((port->FIFO >> 0) & 0x7) << 2); uint8_t rx_water = (rx_fifo_size < 16) ? rx_fifo_size >> 1 : 7; /* Serial.printf("SerialX::begin stat:%x ctrl:%x fifo:%x water:%x\n", port->STAT, port->CTRL, port->FIFO, port->WATER ); Serial.printf(" FIFO sizes: tx:%d rx:%d\n",tx_fifo_size, rx_fifo_size); Serial.printf(" Watermark tx:%d, rx: %d\n", tx_water, rx_water); */ port->WATER = LPUART_WATER_RXWATER(rx_water) | LPUART_WATER_TXWATER(tx_water); port->FIFO |= LPUART_FIFO_TXFE | LPUART_FIFO_RXFE; // lets configure up our CTRL register value uint32_t ctrl = CTRL_TX_INACTIVE; // Now process the bits in the Format value passed in // Bits 0-2 - Parity plus 9 bit. ctrl |= (format & (LPUART_CTRL_PT | LPUART_CTRL_PE) ); // configure parity - turn off PT, PE, M and configure PT, PE if (format & 0x04) ctrl |= LPUART_CTRL_M; // 9 bits (might include parity) if ((format & 0x0F) == 0x04) ctrl |= LPUART_CTRL_R9T8; // 8N2 is 9 bit with 9th bit always 1 // Bit 5 TXINVERT if (format & 0x20) ctrl |= LPUART_CTRL_TXINV; // tx invert // write out computed CTRL port->CTRL = ctrl; // Bit 3 10 bit - Will assume that begin already cleared it. // process some other bits which change other registers. if (format & 0x08) port->BAUD |= LPUART_BAUD_M10; // Bit 4 RXINVERT uint32_t c = port->STAT & ~LPUART_STAT_RXINV; if (format & 0x10) c |= LPUART_STAT_RXINV; // rx invert port->STAT = c; // bit 8 can turn on 2 stop bit mote if ( format & 0x100) port->BAUD |= LPUART_BAUD_SBNS; //Serial.printf(" stat:%x ctrl:%x fifo:%x water:%x\n", port->STAT, port->CTRL, port->FIFO, port->WATER ); enableSerialEvents(); // Enable the processing of serialEvent for this object }; inline void HardwareSerial::rts_assert() { DIRECT_WRITE_LOW(rts_pin_baseReg_, rts_pin_bitmask_); } inline void HardwareSerial::rts_deassert() { DIRECT_WRITE_HIGH(rts_pin_baseReg_, rts_pin_bitmask_); } void HardwareSerial::end(void) { if (!(hardware->ccm_register & hardware->ccm_value)) return; while (transmitting_) yield(); // wait for buffered data to send port->CTRL = 0; // disable the TX and RX ... // Not sure if this is best, but I think most IO pins default to Mode 5? which appears to be digital IO? *(portConfigRegister(hardware->rx_pin)) = 5; *(portConfigRegister(hardware->tx_pin)) = 5; // Might need to clear out other areas as well? rx_buffer_head_ = 0; rx_buffer_tail_ = 0; if (rts_pin_baseReg_) rts_deassert(); // disableSerialEvents(); // disable the processing of serialEvent for this object } void HardwareSerial::transmitterEnable(uint8_t pin) { while (transmitting_) ; pinMode(pin, OUTPUT); transmit_pin_baseReg_ = PIN_TO_BASEREG(pin); transmit_pin_bitmask_ = PIN_TO_BITMASK(pin); DIRECT_WRITE_LOW(transmit_pin_baseReg_, transmit_pin_bitmask_); } void HardwareSerial::setRX(uint8_t pin) { // Currently none of these have multiple // possible RX pins } void HardwareSerial::setTX(uint8_t pin, bool opendrain) { // While all of our TX pins only have one defined pin, we can choose to // turn on or off opendrain mode. if (pin == hardware->tx_pin) { if (opendrain) *(portControlRegister(hardware->tx_pin)) = IOMUXC_PAD_ODE | IOMUXC_PAD_DSE(3) | IOMUXC_PAD_SPEED(3); else *(portControlRegister(hardware->tx_pin)) = IOMUXC_PAD_SRE | IOMUXC_PAD_DSE(3) | IOMUXC_PAD_SPEED(3); } } bool HardwareSerial::attachRts(uint8_t pin) { if (!(hardware->ccm_register & hardware->ccm_value)) return 0; if (pin < CORE_NUM_DIGITAL) { rts_pin_baseReg_ = PIN_TO_BASEREG(pin); rts_pin_bitmask_ = PIN_TO_BITMASK(pin); pinMode(pin, OUTPUT); rts_assert(); } else { rts_pin_baseReg_ = NULL; return 0; } return 1; } bool HardwareSerial::attachCts(uint8_t pin) { if (!(hardware->ccm_register & hardware->ccm_value)) return false; if ((pin != 0xff) && (pin == hardware->cts_pin)) { // Setup the IO pin as weak PULL down. *(portControlRegister(pin)) = IOMUXC_PAD_DSE(7) | IOMUXC_PAD_PKE | IOMUXC_PAD_PUE | IOMUXC_PAD_PUS(0) | IOMUXC_PAD_HYS; *(portConfigRegister(hardware->cts_pin)) = hardware->cts_mux_val; port->MODIR |= LPUART_MODIR_TXCTSE; return true; } else { port->MODIR &= ~LPUART_MODIR_TXCTSE; return false; } } void HardwareSerial::clear(void) { // BUGBUG:: deal with FIFO rx_buffer_head_ = rx_buffer_tail_; if (rts_pin_baseReg_) rts_assert(); } int HardwareSerial::availableForWrite(void) { uint32_t head, tail; head = tx_buffer_head_; tail = tx_buffer_tail_; if (head >= tail) return tx_buffer_total_size_ - 1 - head + tail; return tail - head - 1; } int HardwareSerial::available(void) { uint32_t head, tail; head = rx_buffer_head_; tail = rx_buffer_tail_; if (head >= tail) return head - tail; return rx_buffer_total_size_ + head - tail; } void HardwareSerial::addStorageForRead(void *buffer, size_t length) { rx_buffer_storage_ = (BUFTYPE*)buffer; if (buffer) { rx_buffer_total_size_ = rx_buffer_total_size_ + length; } else { rx_buffer_total_size_ = rx_buffer_total_size_; } rts_low_watermark_ = rx_buffer_total_size_ - hardware->rts_low_watermark; rts_high_watermark_ = rx_buffer_total_size_ - hardware->rts_high_watermark; } void HardwareSerial::addStorageForWrite(void *buffer, size_t length) { tx_buffer_storage_ = (BUFTYPE*)buffer; if (buffer) { tx_buffer_total_size_ = tx_buffer_total_size_ + length; } else { tx_buffer_total_size_ = tx_buffer_total_size_; } } int HardwareSerial::peek(void) { uint32_t head, tail; head = rx_buffer_head_; tail = rx_buffer_tail_; if (head == tail) return -1; if (++tail >= rx_buffer_total_size_) tail = 0; if (tail < rx_buffer_size_) { return rx_buffer_[tail]; } else { return rx_buffer_storage_[tail-rx_buffer_size_]; } } int HardwareSerial::read(void) { uint32_t head, tail; int c; head = rx_buffer_head_; tail = rx_buffer_tail_; if (head == tail) return -1; if (++tail >= rx_buffer_total_size_) tail = 0; if (tail < rx_buffer_size_) { c = rx_buffer_[tail]; } else { c = rx_buffer_storage_[tail-rx_buffer_size_]; } rx_buffer_tail_ = tail; if (rts_pin_baseReg_) { uint32_t avail; if (head >= tail) avail = head - tail; else avail = rx_buffer_total_size_ + head - tail; if (avail <= rts_low_watermark_) rts_assert(); } return c; } void HardwareSerial::flush(void) { while (transmitting_) yield(); // wait } size_t HardwareSerial::write(uint8_t c) { // use the 9 bit version (maybe 10 bit) do do the work. return write9bit(c); } size_t HardwareSerial::write9bit(uint32_t c) { uint32_t head, n; //digitalWrite(3, HIGH); //digitalWrite(5, HIGH); if (transmit_pin_baseReg_) DIRECT_WRITE_HIGH(transmit_pin_baseReg_, transmit_pin_bitmask_); head = tx_buffer_head_; if (++head >= tx_buffer_total_size_) head = 0; while (tx_buffer_tail_ == head) { int priority = nvic_execution_priority(); if (priority <= hardware->irq_priority) { if ((port->STAT & LPUART_STAT_TDRE)) { uint32_t tail = tx_buffer_tail_; if (++tail >= tx_buffer_total_size_) tail = 0; if (tail < tx_buffer_size_) { n = tx_buffer_[tail]; } else { n = tx_buffer_storage_[tail-tx_buffer_size_]; } port->DATA = n; tx_buffer_tail_ = tail; } } else if (priority >= 256) { yield(); // wait } } //digitalWrite(5, LOW); //Serial.printf("WR %x %d %d %d %x %x\n", c, head, tx_buffer_size_, tx_buffer_total_size_, (uint32_t)tx_buffer_, (uint32_t)tx_buffer_storage_); if (head < tx_buffer_size_) { tx_buffer_[head] = c; } else { tx_buffer_storage_[head - tx_buffer_size_] = c; } __disable_irq(); transmitting_ = 1; tx_buffer_head_ = head; port->CTRL |= LPUART_CTRL_TIE; // (may need to handle this issue)BITBAND_SET_BIT(LPUART0_CTRL, TIE_BIT); __enable_irq(); //digitalWrite(3, LOW); return 1; } void HardwareSerial::IRQHandler() { //digitalWrite(4, HIGH); uint32_t head, tail, n; uint32_t ctrl; // See if we have stuff to read in. // Todo - Check idle. if (port->STAT & (LPUART_STAT_RDRF | LPUART_STAT_IDLE)) { // See how many bytes or pending. //digitalWrite(5, HIGH); uint8_t avail = (port->WATER >> 24) & 0x7; if (avail) { uint32_t newhead; head = rx_buffer_head_; tail = rx_buffer_tail_; do { n = port->DATA & 0x3ff; // Use only up to 10 bits of data newhead = head + 1; if (newhead >= rx_buffer_total_size_) newhead = 0; if (newhead != rx_buffer_tail_) { head = newhead; if (newhead < rx_buffer_size_) { rx_buffer_[head] = n; } else { rx_buffer_storage_[head-rx_buffer_size_] = n; } } } while (--avail > 0) ; rx_buffer_head_ = head; if (rts_pin_baseReg_) { uint32_t avail; if (head >= tail) avail = head - tail; else avail = rx_buffer_total_size_ + head - tail; if (avail >= rts_high_watermark_) rts_deassert(); } } // If it was an idle status clear the idle if (port->STAT & LPUART_STAT_IDLE) { port->STAT |= LPUART_STAT_IDLE; // writing a 1 to idle should clear it. } //digitalWrite(5, LOW); } // See if we are transmitting and room in buffer. ctrl = port->CTRL; if ((ctrl & LPUART_CTRL_TIE) && (port->STAT & LPUART_STAT_TDRE)) { //digitalWrite(3, HIGH); head = tx_buffer_head_; tail = tx_buffer_tail_; do { if (head == tail) break; if (++tail >= tx_buffer_total_size_) tail = 0; if (tail < tx_buffer_size_) { n = tx_buffer_[tail]; } else { n = tx_buffer_storage_[tail-tx_buffer_size_]; } port->DATA = n; } while (((port->WATER >> 8) & 0x7) < 4); // need to computer properly tx_buffer_tail_ = tail; if (head == tail) { port->CTRL &= ~LPUART_CTRL_TIE; port->CTRL |= LPUART_CTRL_TCIE; // Actually wondering if we can just leave this one on... } //digitalWrite(3, LOW); } if ((ctrl & LPUART_CTRL_TCIE) && (port->STAT & LPUART_STAT_TC)) { transmitting_ = 0; if (transmit_pin_baseReg_) DIRECT_WRITE_LOW(transmit_pin_baseReg_, transmit_pin_bitmask_); port->CTRL &= ~LPUART_CTRL_TCIE; } //digitalWrite(4, LOW); } void HardwareSerial::processSerialEvents() { if (!serial_event_handlers_active) return; // bail quick if no one processing SerialEvents. uint8_t handlers_still_to_process = serial_event_handlers_active; for (uint8_t i = 0; i < 8; i++) { if (serial_event_handler_checks[i]) { (*serial_event_handler_checks[i])(); if (--handlers_still_to_process == 0) return; } } } void HardwareSerial::enableSerialEvents() { if (!serial_event_handler_checks[hardware->serial_index]) { serial_event_handler_checks[hardware->serial_index] = hardware->serial_event_handler_check; // clear it out serial_event_handlers_active++; } } void HardwareSerial::disableSerialEvents() { if (serial_event_handler_checks[hardware->serial_index]) { serial_event_handler_checks[hardware->serial_index] = nullptr; // clear it out serial_event_handlers_active--; } }