circuitpython/ports/esp32s2/peripherals/pcnt.c

69 lines
2.2 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2020 microDev
*
* 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 "peripherals/pcnt.h"
#define PCNT_UNIT_ACTIVE 1
#define PCNT_UNIT_INACTIVE 0
static uint8_t pcnt_unit_state[4];
void peripherals_pcnt_reset(void) {
for (uint8_t i = 0; i<=3; i++) {
pcnt_unit_state[i] = PCNT_UNIT_INACTIVE;
}
}
int peripherals_pcnt_init(pcnt_config_t pcnt_config) {
// Look for available pcnt unit
for (uint8_t i = 0; i<=3; i++) {
if (pcnt_unit_state[i] == PCNT_UNIT_INACTIVE) {
pcnt_config.unit = (pcnt_unit_t)i;
pcnt_unit_state[i] = PCNT_UNIT_ACTIVE;
break;
} else if (i == 3) {
return -1;
}
}
// Initialize PCNT unit
pcnt_unit_config(&pcnt_config);
// Initialize PCNT's counter
pcnt_counter_pause(pcnt_config.unit);
pcnt_counter_clear(pcnt_config.unit);
// Everything is set up, now go to counting
pcnt_counter_resume(pcnt_config.unit);
return pcnt_config.unit;
}
void peripherals_pcnt_deinit(pcnt_unit_t* unit) {
pcnt_unit_state[*unit] = PCNT_UNIT_INACTIVE;
*unit = PCNT_UNIT_MAX;
}