lpc1xxx/LPC1xxx_startup.c

   1 /*
   2  * Software License Agreement (BSD License)
   3  *
   4  * Copyright (c) 2010, Roel Verdult
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  * notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  * notice, this list of conditions and the following disclaimer in the
  13  * documentation and/or other materials provided with the distribution.
  14  * 3. Neither the name of the copyright holders nor the
  15  * names of its contributors may be used to endorse or promote products
  16  * derived from this software without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ''AS IS'' AND ANY
  19  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  20  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  21  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
  22  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  23  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  24  *  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  25  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  27  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  *
  29  */
  30
  31 // These are defined and created by the linker, locating them in memory
  32 extern unsigned char _etext;
  33 extern unsigned char _data;
  34 extern unsigned char _edata;
  35 extern unsigned char _bss;
  36 extern unsigned char _ebss;
  37
  38 // Prototype the required startup functions
  39 extern void main(void);
  40
  41 // The entry point of the application, prepare segments,
  42 // initialize the cpu and execute main()
  43 void boot_entry(void)
  44 {
  45   register unsigned char *src, *dst;
  46
  47   // Get physical data address and copy it to sram
  48   src = &_etext;
  49   dst = &_data;
  50   while(dst < &_edata) {
  51     *dst++ = *src++;
  52   }
  53
  54   // Clear the bss segment
  55   dst = &_bss;
  56   while(dst < &_ebss) {
  57     *dst++ = 0;
  58   }
  59
  60   // Execute the code at the program entry point
  61   main();
  62
  63   // Do nothing when returned from main, just keep looping
  64   while(1);
  65 }