jump_bootloader.c

   1 // this code from:
   2 // http://www.pjrc.com/teensy/jump_to_bootloader.html
   3 #include <avr/io.h>
   4 #include <avr/interrupt.h>
   5 #include <util/delay.h>
   6
   7 void jump_bootloader(void) {
   8     cli();
   9     // disable watchdog, if enabled
  10     // disable all peripherals
  11     UDCON = 1;
  12     USBCON = (1<<FRZCLK);  // disable USB
  13     UCSR1B = 0;
  14     _delay_ms(5);
  15 #if defined(__AVR_AT90USB162__)                // Teensy 1.0
  16     DDRB = 0; DDRC = 0; DDRD = 0;
  17     TIMSK0 = 0; TIMSK1 = 0;
  18     asm volatile("jmp 0x1F00");
  19 #elif defined(__AVR_ATmega32U4__)              // Teensy 2.0
  20     DDRB = 0; DDRC = 0; DDRD = 0; DDRE = 0; DDRF = 0;
  21     TIMSK0 = 0; TIMSK1 = 0; TIMSK3 = 0; TIMSK4 = 0;
  22     ADCSRA = 0;
  23     asm volatile("jmp 0x3F00");
  24 #elif defined(__AVR_AT90USB646__)              // Teensy++ 1.0
  25     DDRA = 0; DDRB = 0; DDRC = 0; DDRD = 0; DDRE = 0; DDRF = 0;
  26     TIMSK0 = 0; TIMSK1 = 0; TIMSK2 = 0; TIMSK3 = 0;
  27     ADCSRA = 0;
  28     asm volatile("jmp 0x7E00");
  29 #elif defined(__AVR_AT90USB1286__)             // Teensy++ 2.0
  30     DDRA = 0; DDRB = 0; DDRC = 0; DDRD = 0; DDRE = 0; DDRF = 0;
  31     TIMSK0 = 0; TIMSK1 = 0; TIMSK2 = 0; TIMSK3 = 0;
  32     ADCSRA = 0;
  33     asm volatile("jmp 0xFE00");
  34 #endif
  35 }