f28f8ba568
This was done to allow greatly granularity when deciding what functionality is built into each board's build. For example, this way pulseio can be omitted to allow for something else such as touchio.
81 lines
3.5 KiB
C
81 lines
3.5 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 "common-hal/microcontroller/types.h"
|
|
#include "shared-bindings/bitbangio/OneWire.h"
|
|
#include "shared-bindings/microcontroller/__init__.h"
|
|
#include "shared-bindings/digitalio/DigitalInOut.h"
|
|
#include "shared-module/bitbangio/types.h"
|
|
|
|
// Durations are taken from here: https://www.maximintegrated.com/en/app-notes/index.mvp/id/126
|
|
|
|
void shared_module_bitbangio_onewire_construct(bitbangio_onewire_obj_t* self,
|
|
const mcu_pin_obj_t* pin) {
|
|
self->pin.base.type = &digitalio_digitalinout_type;
|
|
common_hal_digitalio_digitalinout_construct(&self->pin, pin);
|
|
}
|
|
|
|
void shared_module_bitbangio_onewire_deinit(bitbangio_onewire_obj_t* self) {
|
|
common_hal_digitalio_digitalinout_deinit(&self->pin);
|
|
}
|
|
|
|
bool shared_module_bitbangio_onewire_reset(bitbangio_onewire_obj_t* self) {
|
|
common_hal_mcu_disable_interrupts();
|
|
common_hal_digitalio_digitalinout_switch_to_output(&self->pin, false, DRIVE_MODE_OPEN_DRAIN);
|
|
common_hal_mcu_delay_us(480);
|
|
common_hal_digitalio_digitalinout_switch_to_input(&self->pin, PULL_NONE);
|
|
common_hal_mcu_delay_us(70);
|
|
bool value = common_hal_digitalio_digitalinout_get_value(&self->pin);
|
|
common_hal_mcu_delay_us(410);
|
|
common_hal_mcu_enable_interrupts();
|
|
return value;
|
|
}
|
|
|
|
bool shared_module_bitbangio_onewire_read_bit(bitbangio_onewire_obj_t* self) {
|
|
common_hal_mcu_disable_interrupts();
|
|
common_hal_digitalio_digitalinout_switch_to_output(&self->pin, false, DRIVE_MODE_OPEN_DRAIN);
|
|
common_hal_mcu_delay_us(6);
|
|
common_hal_digitalio_digitalinout_switch_to_input(&self->pin, PULL_NONE);
|
|
// TODO(tannewt): Test with more devices and maybe make the delays
|
|
// configurable. This should be 9 by the datasheet but all bits read as 1
|
|
// then.
|
|
common_hal_mcu_delay_us(6);
|
|
bool value = common_hal_digitalio_digitalinout_get_value(&self->pin);
|
|
common_hal_mcu_delay_us(55);
|
|
common_hal_mcu_enable_interrupts();
|
|
return value;
|
|
}
|
|
|
|
void shared_module_bitbangio_onewire_write_bit(bitbangio_onewire_obj_t* self,
|
|
bool bit) {
|
|
common_hal_mcu_disable_interrupts();
|
|
common_hal_digitalio_digitalinout_switch_to_output(&self->pin, false, DRIVE_MODE_OPEN_DRAIN);
|
|
common_hal_mcu_delay_us(bit? 6 : 60);
|
|
common_hal_digitalio_digitalinout_switch_to_input(&self->pin, PULL_NONE);
|
|
common_hal_mcu_delay_us(bit? 64 : 10);
|
|
common_hal_mcu_enable_interrupts();
|
|
}
|