circuitpython/atmel-samd/reset.c
Scott Shawcroft 5d732f45bb atmel-samd: Reboot to bootloader when a 1200 baud serial connection is
closed. This is how Arduino triggers the bootloader.
2017-07-06 13:41:13 -07:00

41 lines
1.7 KiB
C

/*
* This file is part of the Micro Python project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2017 Scott Shawcroft for Adafruit Industries
*
* 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:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* 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 "flash_api.h"
#include "reset.h"
#include "asf/sam0/utils/cmsis/samd21/include/samd21.h"
// Copied from inc/uf2.h in https://github.com/Microsoft/uf2-samd21
#define DBL_TAP_PTR ((volatile uint32_t *)(HMCRAMC0_ADDR + HMCRAMC0_SIZE - 4))
#define DBL_TAP_MAGIC 0xf01669ef // Randomly selected, adjusted to have first and last bit set
void reset_to_bootloader(void) {
flash_flush();
*DBL_TAP_PTR = DBL_TAP_MAGIC;
NVIC_SystemReset();
}