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/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2015-2016 Damien P. George
*
* 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 "esponewire.h"
#define TIMING_RESET1 (0)
#define TIMING_RESET2 (1)
#define TIMING_RESET3 (2)
#define TIMING_READ1 (3)
#define TIMING_READ2 (4)
#define TIMING_READ3 (5)
#define TIMING_WRITE1 (6)
#define TIMING_WRITE2 (7)
#define TIMING_WRITE3 (8)
uint16_t esp_onewire_timings[9] = {480, 40, 420, 5, 5, 40, 10, 50, 10};
int esp_onewire_reset(mp_hal_pin_obj_t pin) {
mp_hal_pin_write(pin, 0);
mp_hal_delay_us(esp_onewire_timings[TIMING_RESET1]);
uint32_t i = mp_hal_quiet_timing_enter();
mp_hal_pin_write(pin, 1);
mp_hal_delay_us_fast(esp_onewire_timings[TIMING_RESET2]);
int status = !mp_hal_pin_read(pin);
mp_hal_quiet_timing_exit(i);
mp_hal_delay_us(esp_onewire_timings[TIMING_RESET3]);
return status;
}
int esp_onewire_readbit(mp_hal_pin_obj_t pin) {
mp_hal_pin_write(pin, 1);
uint32_t i = mp_hal_quiet_timing_enter();
mp_hal_pin_write(pin, 0);
mp_hal_delay_us_fast(esp_onewire_timings[TIMING_READ1]);
mp_hal_pin_write(pin, 1);
mp_hal_delay_us_fast(esp_onewire_timings[TIMING_READ2]);
int value = mp_hal_pin_read(pin);
mp_hal_quiet_timing_exit(i);
mp_hal_delay_us_fast(esp_onewire_timings[TIMING_READ3]);
return value;
}
void esp_onewire_writebit(mp_hal_pin_obj_t pin, int value) {
uint32_t i = mp_hal_quiet_timing_enter();
mp_hal_pin_write(pin, 0);
mp_hal_delay_us_fast(esp_onewire_timings[TIMING_WRITE1]);
if (value) {
mp_hal_pin_write(pin, 1);
}
mp_hal_delay_us_fast(esp_onewire_timings[TIMING_WRITE2]);
mp_hal_pin_write(pin, 1);
mp_hal_delay_us_fast(esp_onewire_timings[TIMING_WRITE3]);
mp_hal_quiet_timing_exit(i);
}
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