text: /* 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 <Arduino.h>
  #include "core/teensy4x/HardwareSerial.h"
  
  #ifndef SERIAL3_TX_BUFFER_SIZE
  #define SERIAL3_TX_BUFFER_SIZE     40 // number of outgoing bytes to buffer
  #endif
  #ifndef SERIAL3_RX_BUFFER_SIZE
  #define SERIAL3_RX_BUFFER_SIZE     64 // number of incoming bytes to buffer
  #endif
  #define IRQ_PRIORITY  64  // 0 = highest priority, 255 = lowest
  
  void IRQHandler_Serial3()
  {
  	Serial3.IRQHandler();
  }
  
  // Serial3
  static BUFTYPE tx_buffer3[SERIAL3_TX_BUFFER_SIZE];
  static BUFTYPE rx_buffer3[SERIAL3_RX_BUFFER_SIZE];
  uint8_t _serialEvent3_default __attribute__((weak)) PROGMEM = 0 ;
  
  static HardwareSerial::hardware_t UART2_Hardware = {
  	2, IRQ_LPUART2, &IRQHandler_Serial3, 
  	&serialEvent3, &_serialEvent3_default,
  	CCM_CCGR0, CCM_CCGR0_LPUART2(CCM_CCGR_ON), 
  	{{15,2, &IOMUXC_LPUART2_RX_SELECT_INPUT, 1}, {0xff, 0xff, nullptr, 0}},
  	{{14,2, &IOMUXC_LPUART2_TX_SELECT_INPUT, 1}, {0xff, 0xff, nullptr, 0}},
  	19, //IOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B1_00, // 19
  	2, // page 473 
  	IRQ_PRIORITY, 38, 24, // IRQ, rts_low_watermark, rts_high_watermark
  	XBARA1_OUT_LPUART2_TRG_INPUT
  };
  HardwareSerial Serial3(&IMXRT_LPUART2, &UART2_Hardware,tx_buffer3, SERIAL3_TX_BUFFER_SIZE,
  	rx_buffer3,  SERIAL3_RX_BUFFER_SIZE);
  
  