text: /*
   * Copyright (c) 2014-2016 IBM Corporation.
   * All rights reserved.
   *
   *  Redistribution and use in source and binary forms, with or without
   *  modification, are permitted provided that the following conditions are met:
   *  * Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   *  * Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   *  * Neither the name of the <organization> nor the
   *    names of its contributors may be used to endorse or promote products
   *    derived from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
   * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
   * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
   * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
   * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
   * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #include "hw.h"
  #include "debug.h"
  #include "lmic.h"
  
  #define LED_PORT        GPIOA // use GPIO PA8 (LED4 on IMST, P11/PPS/EXT1_10/GPS6 on Blipper)
  #define LED_PIN         8
  #define USART_TX_PORT   GPIOA
  #define USART_TX_PIN    9
  #define GPIO_AF_USART1  0x07
  
  void debug_init () {
      // configure LED pin as output
      hw_cfg_pin(LED_PORT, LED_PIN, GPIOCFG_MODE_OUT | GPIOCFG_OSPEED_40MHz | GPIOCFG_OTYPE_PUPD | GPIOCFG_PUPD_PUP);
      debug_led(0);
  
      // configure USART1 (115200/8N1, tx-only)
      RCC->APB2ENR |= RCC_APB2ENR_USART1EN;
      hw_cfg_pin(USART_TX_PORT, USART_TX_PIN, GPIOCFG_MODE_ALT|GPIOCFG_OSPEED_40MHz|GPIOCFG_OTYPE_PUPD|GPIOCFG_PUPD_PUP|GPIO_AF_USART1);
      USART1->BRR = 277; // 115200
      USART1->CR1 = USART_CR1_UE | USART_CR1_TE; // usart+transmitter enable
  
      // print banner
      debug_str("\r\n============== DEBUG STARTED ==============\r\n");
  }
  
  void debug_led (int val) {
      hw_set_pin(LED_PORT, LED_PIN, val);
  }
  
  void debug_char (char c) {
      while( !(USART1->SR & USART_SR_TXE) );    
      USART1->DR = c;
  }
  
  void debug_hex (u1_t b) {
      debug_char("0123456789ABCDEF"[b>>4]);
      debug_char("0123456789ABCDEF"[b&0xF]);
  }
  
  void debug_buf (const u1_t* buf, int len) {
      while(len--) {
          debug_hex(*buf++);
          debug_char(' ');
      }
      debug_char('\r');
      debug_char('\n');
  }
  
  void debug_uint (u4_t v) {
      for(s1_t n=24; n>=0; n-=8) {
          debug_hex(v>>n);
      }
  }
  
  void debug_int (s4_t v) {
      char buf[10], *p = buf;
      int n = debug_fmt(buf, sizeof(buf), v, 10, 0, 0);
      while(n--)
          debug_char(*p++);
  }
  
  void debug_str (const char* str) {
      while(*str) {
          debug_char(*str++);
      }
  }
  
  void debug_val (const char* label, u4_t val) {
      debug_str(label);
      debug_uint(val);
      debug_char('\r');
      debug_char('\n');
  }
  
  void debug_valdec (const char* label, s4_t val) {
      debug_str(label);
      debug_int(val);
      debug_char('\r');
      debug_char('\n');
  }
  
  int debug_fmt (char* buf, int max, s4_t val, int base, int width, char pad) {
      char num[33], *p = num, *b = buf;
      u4_t m, v;
      // special handling of negative decimals
      v = (base == 10 && val < 0) ? -val : val;
      // generate digits backwards
      do {
          *p++ = ((m=v%base) <= 9) ? m+'0' : m+'A'-10;
      } while( v /= base );
      // prefix negative decimals with '-'
      if(base == 10 && val < 0) {
          *p++ = '-';
      }
      // add leading zeroes or spaces
      while( b-buf < max-1 && b-buf < width-(p-num) ) {
          *b++ = pad;
      }
      // copy digits and sign forwards
      do *b++ = *--p;
      while( b-buf < max && p > num );
      // return number of characters written
      return b - buf;
  }
  
  void debug_event (int ev) {
      static const char* evnames[] = {
          [EV_SCAN_TIMEOUT]   = "SCAN_TIMEOUT",
          [EV_BEACON_FOUND]   = "BEACON_FOUND",
          [EV_BEACON_MISSED]  = "BEACON_MISSED",
          [EV_BEACON_TRACKED] = "BEACON_TRACKED",
          [EV_JOINING]        = "JOINING",
          [EV_JOINED]         = "JOINED",
          [EV_RFU1]           = "RFU1",
          [EV_JOIN_FAILED]    = "JOIN_FAILED",
          [EV_REJOIN_FAILED]  = "REJOIN_FAILED",
          [EV_TXCOMPLETE]     = "TXCOMPLETE",
          [EV_LOST_TSYNC]     = "LOST_TSYNC",
          [EV_RESET]          = "RESET",
          [EV_RXCOMPLETE]     = "RXCOMPLETE",
          [EV_LINK_DEAD]      = "LINK_DEAD",
          [EV_LINK_ALIVE]     = "LINK_ALIVE",
          [EV_SCAN_FOUND]     = "SCAN_FOUND",
          [EV_TXSTART]        = "EV_TXSTART",
      };
      debug_str((ev < sizeof(evnames)/sizeof(evnames[0])) ? evnames[ev] : "EV_UNKNOWN" );
      debug_char('\r');
      debug_char('\n');
  }
  