keychron_qmk_firmware/pjrc/jump_bootloader.c
2011-02-22 03:08:59 +09:00

41 lines
1.7 KiB
C

// this code from:
// http://www.pjrc.com/teensy/jump_to_bootloader.html
#include <avr/io.h>
#include <avr/interrupt.h>
#include <util/delay.h>
void jump_bootloader(void) {
cli();
// disable watchdog, if enabled
// disable all peripherals
UDCON = 1;
USBCON = (1<<FRZCLK); // disable USB
UCSR1B = 0;
_delay_ms(5);
#if defined(__AVR_AT90USB162__) // Teensy 1.0
EIMSK = 0; PCICR = 0; SPCR = 0; ACSR = 0; EECR = 0;
TIMSK0 = 0; TIMSK1 = 0; UCSR1B = 0;
DDRB = 0; DDRC = 0; DDRD = 0;
PORTB = 0; PORTC = 0; PORTD = 0;
asm volatile("jmp 0x3E00");
#elif defined(__AVR_ATmega32U4__) // Teensy 2.0
EIMSK = 0; PCICR = 0; SPCR = 0; ACSR = 0; EECR = 0; ADCSRA = 0;
TIMSK0 = 0; TIMSK1 = 0; TIMSK3 = 0; TIMSK4 = 0; UCSR1B = 0; TWCR = 0;
DDRB = 0; DDRC = 0; DDRD = 0; DDRE = 0; DDRF = 0; TWCR = 0;
PORTB = 0; PORTC = 0; PORTD = 0; PORTE = 0; PORTF = 0;
asm volatile("jmp 0x7E00");
#elif defined(__AVR_AT90USB646__) // Teensy++ 1.0
EIMSK = 0; PCICR = 0; SPCR = 0; ACSR = 0; EECR = 0; ADCSRA = 0;
TIMSK0 = 0; TIMSK1 = 0; TIMSK2 = 0; TIMSK3 = 0; UCSR1B = 0; TWCR = 0;
DDRA = 0; DDRB = 0; DDRC = 0; DDRD = 0; DDRE = 0; DDRF = 0;
PORTA = 0; PORTB = 0; PORTC = 0; PORTD = 0; PORTE = 0; PORTF = 0;
asm volatile("jmp 0xFC00");
#elif defined(__AVR_AT90USB1286__) // Teensy++ 2.0
EIMSK = 0; PCICR = 0; SPCR = 0; ACSR = 0; EECR = 0; ADCSRA = 0;
TIMSK0 = 0; TIMSK1 = 0; TIMSK2 = 0; TIMSK3 = 0; UCSR1B = 0; TWCR = 0;
DDRA = 0; DDRB = 0; DDRC = 0; DDRD = 0; DDRE = 0; DDRF = 0;
PORTA = 0; PORTB = 0; PORTC = 0; PORTD = 0; PORTE = 0; PORTF = 0;
asm volatile("jmp 0x1FC00");
#endif
}