circuitpython/cc3200/mods/pybadc.c

196 lines
6.2 KiB
C

/*
* This file is part of the Micro Python project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2013, 2014 Damien P. George
* Copyright (c) 2015 Daniel Campora
*
* 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 <string.h>
#include "py/mpconfig.h"
#include MICROPY_HAL_H
#include "py/nlr.h"
#include "py/runtime.h"
#include "py/binary.h"
#include "py/gc.h"
#include "bufhelper.h"
#include "inc/hw_types.h"
#include "inc/hw_adc.h"
#include "inc/hw_ints.h"
#include "inc/hw_memmap.h"
#include "rom_map.h"
#include "interrupt.h"
#include "pin.h"
#include "gpio.h"
#include "prcm.h"
#include "adc.h"
#include "pybadc.h"
#include "pybpin.h"
#include "pybsleep.h"
#include "pins.h"
#include "mpexception.h"
/// \moduleref pyb
/// \class ADC - analog to digital conversion: read analog values on a pin
///
/// Usage:
///
/// adc = pyb.ADC(channel) # create an adc object on the given channel (0 to 3)
/// this automatically configures the pin associated to
/// that analog channel.
/// adc.read() # read channel value
///
/// The sample rate is fixed to 62.5KHz and the resolution to 12 bits.
typedef struct _pyb_obj_adc_t {
mp_obj_base_t base;
byte channel;
byte num;
} pyb_obj_adc_t;
STATIC void pybadc_init (pyb_obj_adc_t *self) {
// enable the ADC channel
MAP_ADCChannelEnable(ADC_BASE, self->channel);
// enable and configure the timer
MAP_ADCTimerConfig(ADC_BASE, (1 << 17) - 1);
MAP_ADCTimerEnable(ADC_BASE);
// enable the ADC peripheral
MAP_ADCEnable(ADC_BASE);
}
/******************************************************************************/
/* Micro Python bindings : adc object */
STATIC void adc_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t self_in, mp_print_kind_t kind) {
pyb_obj_adc_t *self = self_in;
print(env, "<ADC, channel=%u>", self->num);
}
/// \classmethod \constructor(channel)
/// Create an ADC object associated with the given channel.
/// This allows you to then read analog values on that pin.
STATIC mp_obj_t adc_make_new(mp_obj_t type_in, mp_uint_t n_args, mp_uint_t n_kw, const mp_obj_t *args) {
// check number of arguments
mp_arg_check_num(n_args, n_kw, 1, 1, false);
// the first argument is the channel number
uint num = mp_obj_get_int(args[0]);
const pin_obj_t *pin;
uint channel;
switch (num) {
case 0:
channel = ADC_CH_0;
pin = &pin_GPIO2;
break;
case 1:
channel = ADC_CH_1;
pin = &pin_GPIO3;
break;
case 2:
channel = ADC_CH_2;
pin = &pin_GPIO4;
break;
case 3:
channel = ADC_CH_3;
pin = &pin_GPIO5;
break;
default:
nlr_raise(mp_obj_new_exception_msg(&mp_type_ValueError, mpexception_value_invalid_arguments));
break;
}
// disable the callback before re-configuring
pyb_obj_adc_t *self = m_new_obj_with_finaliser(pyb_obj_adc_t);
self->base.type = &pyb_adc_type;
self->channel = channel;
self->num = num;
// configure the pin in analog mode
pin_config ((pin_obj_t *)pin, PIN_MODE_0, GPIO_DIR_MODE_IN, PYBPIN_ANALOG_TYPE, PIN_STRENGTH_2MA);
// initialize it
pybadc_init (self);
// register it with the sleep module
pybsleep_add ((const mp_obj_t)self, (WakeUpCB_t)pybadc_init);
return self;
}
/// \method read()
/// Read the value on the analog pin and return it. The returned value
/// will be between 0 and 4095.
STATIC mp_obj_t adc_read(mp_obj_t self_in) {
pyb_obj_adc_t *self = self_in;
uint32_t sample;
// wait until a new value is available
while (!MAP_ADCFIFOLvlGet(ADC_BASE, self->channel));
// read the sample
sample = MAP_ADCFIFORead(ADC_BASE, self->channel);
// the 12 bit sampled value is stored in bits [13:2]
return MP_OBJ_NEW_SMALL_INT((sample & 0x3FFF) >> 2);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(adc_read_obj, adc_read);
/// \method enable()
/// Enable the adc channel
STATIC mp_obj_t adc_enable(mp_obj_t self_in) {
pyb_obj_adc_t *self = self_in;
MAP_ADCChannelEnable(ADC_BASE, self->channel);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(adc_enable_obj, adc_enable);
/// \method disable()
/// Disable the adc channel
STATIC mp_obj_t adc_disable(mp_obj_t self_in) {
pyb_obj_adc_t *self = self_in;
MAP_ADCChannelDisable(ADC_BASE, self->channel);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(adc_disable_obj, adc_disable);
STATIC const mp_map_elem_t adc_locals_dict_table[] = {
{ MP_OBJ_NEW_QSTR(MP_QSTR___del__), (mp_obj_t)&adc_disable_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_read), (mp_obj_t)&adc_read_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_enable), (mp_obj_t)&adc_enable_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_disable), (mp_obj_t)&adc_disable_obj },
};
STATIC MP_DEFINE_CONST_DICT(adc_locals_dict, adc_locals_dict_table);
const mp_obj_type_t pyb_adc_type = {
{ &mp_type_type },
.name = MP_QSTR_ADC,
.print = adc_print,
.make_new = adc_make_new,
.locals_dict = (mp_obj_t)&adc_locals_dict,
};