/*

* This file is part of the Micro Python project, http://micropython.org/

*

* The MIT License (MIT)

*

* Copyright (c) 2013, 2014 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 <stdio.h>

#include <stdint.h>

#include <string.h>

#include "py/runtime.h"

#include "modmachine_dac.h"

#include "asf/sam0/drivers/dac/dac.h"

/// \moduleref machine

/// \class DAC - digital to analog conversion

///

/// The DAC is used to output analog values (a specific voltage) on pin PA02

/// (Arduino Zero A0, Feather MO Bluefruit A0).

/// The voltage will be between 0 and 3.3V.

///

/// *This module will undergo changes to the API.*

///

/// Example usage:

///

/// from machine import DAC

///

/// dac = DAC() # create DAC 1 on pin PA02

/// dac.write(512) # write a value to the DAC (makes PA02 1.65V)

/// dac.write_mv(1650) # Also results in PA02 being 1.65V

/******************************************************************************/

// Micro Python bindings

typedef struct _dac_obj_t {

mp_obj_base_t base;

struct dac_module dac_instance;

} dac_obj_t;

// create the dac object

/// \classmethod \constructor()

/// Construct a new DAC object for pin PA02.

STATIC mp_obj_t dac_make_new(const mp_obj_type_t *type, mp_uint_t n_args, mp_uint_t n_kw, const mp_obj_t *args) {

// check arguments

mp_arg_check_num(n_args, n_kw, 0, MP_OBJ_FUN_ARGS_MAX, true);

dac_obj_t *dac = m_new_obj(dac_obj_t);

dac->base.type = &dac_type;

struct dac_config config_dac;

dac_get_config_defaults(&config_dac);

config_dac.reference = DAC_REFERENCE_AVCC;

enum status_code status = dac_init(&dac->dac_instance, DAC, &config_dac);

if (status != STATUS_OK) {

// Throw error.

return mp_const_none;

}

struct dac_chan_config config_dac_chan;

dac_chan_get_config_defaults(&config_dac_chan);

dac_chan_set_config(&dac->dac_instance, DAC_CHANNEL_0, &config_dac_chan);

dac_chan_enable(&dac->dac_instance, DAC_CHANNEL_0);

dac_enable(&dac->dac_instance);

// return object

return dac;

}

/// \method deinit()

/// Turn off the DAC, enable other use of pin.

STATIC mp_obj_t dac_del(mp_obj_t self_in) {

dac_obj_t *self = self_in;

dac_disable(&self->dac_instance);

dac_chan_disable(&self->dac_instance, DAC_CHANNEL_0);

return mp_const_none;

}

STATIC MP_DEFINE_CONST_FUN_OBJ_1(dac_del_obj, dac_del);

/// \method write(value)

/// Direct access to the DAC output (10 bit).

STATIC mp_obj_t dac_write(mp_obj_t self_in, mp_obj_t val) {

dac_obj_t *self = self_in;

dac_chan_write(&self->dac_instance, DAC_CHANNEL_0, mp_obj_get_int(val));

return mp_const_none;

}

STATIC MP_DEFINE_CONST_FUN_OBJ_2(dac_write_obj, dac_write);

/// \method write_mv(value)

/// Direct access to the DAC output by specifying millivolts.

STATIC mp_obj_t dac_write_mv(mp_obj_t self_in, mp_obj_t val_mv) {

dac_obj_t *self = self_in;

// TODO(tannewt): Sanity check that the mv value is less than the reference

// voltage.

// Dividing by 3301 instead of 3300 ensures that val_mv of 3300 actually

// produces a value of 1023 instead of 1024 which is out of range of the

// DAC.

uint16_t val = ((uint32_t) mp_obj_get_int(val_mv)) * 1024 / 3301;

dac_chan_write(&self->dac_instance, DAC_CHANNEL_0, val);

return mp_const_none;

}

STATIC MP_DEFINE_CONST_FUN_OBJ_2(dac_write_mv_obj, dac_write_mv);

STATIC const mp_map_elem_t dac_locals_dict_table[] = {

// instance methods

{ MP_OBJ_NEW_QSTR(MP_QSTR___del__), (mp_obj_t)&dac_del_obj },

{ MP_OBJ_NEW_QSTR(MP_QSTR_write), (mp_obj_t)&dac_write_obj },

{ MP_OBJ_NEW_QSTR(MP_QSTR_write_mv), (mp_obj_t)&dac_write_mv_obj },

};

STATIC MP_DEFINE_CONST_DICT(dac_locals_dict, dac_locals_dict_table);

const mp_obj_type_t dac_type = {

{ &mp_type_type },

.name = MP_QSTR_DAC,

.make_new = dac_make_new,

.locals_dict = (mp_obj_t)&dac_locals_dict,

};