circuitpython/ports/nrf/boards/pca10056/board.c

86 lines
2.6 KiB
C

/*
* This file is part of the MicroPython 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 <string.h>
#include <stdbool.h>
#include "nrf.h"
#include "boards/board.h"
volatile uint32_t ticks_ms = 0;
#define HAL_LFCLK_FREQ (32768UL)
#define HAL_RTC_FREQ (1024UL)
#define HAL_RTC_COUNTER_PRESCALER ((HAL_LFCLK_FREQ/HAL_RTC_FREQ)-1)
/* Maximum RTC ticks */
#define portNRF_RTC_MAXTICKS ((1U<<24)-1U)
void board_init(void)
{
// 32Khz XTAL
NRF_CLOCK->LFCLKSRC = (uint32_t)((CLOCK_LFCLKSRC_SRC_Xtal << CLOCK_LFCLKSRC_SRC_Pos) & CLOCK_LFCLKSRC_SRC_Msk);
NRF_CLOCK->TASKS_LFCLKSTART = 1UL;
// Set up RTC1 as tick timer
NVIC_DisableIRQ(RTC1_IRQn);
NRF_RTC1->EVTENCLR = RTC_EVTEN_COMPARE0_Msk;
NRF_RTC1->INTENCLR = RTC_INTENSET_COMPARE0_Msk;
NRF_RTC1->TASKS_STOP = 1;
NRF_RTC1->TASKS_CLEAR = 1;
ticks_ms = 0;
NRF_RTC1->PRESCALER = HAL_RTC_COUNTER_PRESCALER;
NRF_RTC1->INTENSET = RTC_INTENSET_TICK_Msk;
NRF_RTC1->TASKS_START = 1;
NRF_RTC1->EVTENSET = RTC_EVTEN_OVRFLW_Msk;
NVIC_SetPriority(RTC1_IRQn, 0xf); // lowest priority
NVIC_EnableIRQ(RTC1_IRQn);
}
void RTC1_IRQHandler(void)
{
// Clear event
NRF_RTC1->EVENTS_TICK = 0;
volatile uint32_t dummy = NRF_RTC1->EVENTS_TICK;
(void) dummy;
//
//// Tick correction
uint32_t systick_counter = NRF_RTC1->COUNTER;
uint32_t diff = (systick_counter - ticks_ms) & portNRF_RTC_MAXTICKS;
ticks_ms += diff;
}
bool board_requests_safe_mode(void) {
return false;
}
void reset_board(void) {
}