mbed-os/targets/TARGET_Maxim/TARGET_MAX32630/mxc/adc.c

181 lines
5.7 KiB
C

/**
* @file
* @brief This file contains the function implementations for the Analog to
* Digital Converter (ADC) peripheral module.
*/
/* ****************************************************************************
* Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved.
*
* 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 MAXIM INTEGRATED 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.
*
* Except as contained in this notice, the name of Maxim Integrated
* Products, Inc. shall not be used except as stated in the Maxim Integrated
* Products, Inc. Branding Policy.
*
* The mere transfer of this software does not imply any licenses
* of trade secrets, proprietary technology, copyrights, patents,
* trademarks, maskwork rights, or any other form of intellectual
* property whatsoever. Maxim Integrated Products, Inc. retains all
* ownership rights.
*
* $Date: 2016-09-09 12:50:50 -0500 (Fri, 09 Sep 2016) $
* $Revision: 24349 $
*
*************************************************************************** */
/**
* @ingroup adc
* @{
*/
/* **** Includes **** */
#include "mxc_config.h"
#include "mxc_assert.h"
#include "mxc_sys.h"
#include "adc.h"
/* **** Definitions **** */
/* **** Globals **** */
/* **** Functions **** */
/* ************************************************************************* */
int ADC_Init(void)
{
int err;
if ((err = SYS_ADC_Init()) != E_NO_ERROR) {
return err;
}
/* Wipe previous configuration */
MXC_ADC->intr = 0;
/* Clear all ADC interrupt flags (W1C) */
MXC_ADC->intr = MXC_ADC->intr;
/* Enable done interrupt */
MXC_ADC->intr = MXC_F_ADC_INTR_ADC_DONE_IE;
/* Power up the ADC */
MXC_ADC->ctrl = (MXC_F_ADC_CTRL_ADC_PU |
MXC_F_ADC_CTRL_ADC_CLK_EN |
MXC_F_ADC_CTRL_BUF_PU |
MXC_F_ADC_CTRL_ADC_REFBUF_PU |
MXC_F_ADC_CTRL_ADC_CHGPUMP_PU);
return E_NO_ERROR;
}
/* ************************************************************************* */
void ADC_StartConvert(mxc_adc_chsel_t channel, unsigned int adc_scale, unsigned int bypass)
{
uint32_t ctrl_tmp;
/* Clear the ADC done flag */
ADC_ClearFlags(MXC_F_ADC_INTR_ADC_DONE_IF);
/* Insert channel selection */
ctrl_tmp = MXC_ADC->ctrl;
ctrl_tmp &= ~(MXC_F_ADC_CTRL_ADC_CHSEL);
ctrl_tmp |= ((channel << MXC_F_ADC_CTRL_ADC_CHSEL_POS) & MXC_F_ADC_CTRL_ADC_CHSEL);
/* Clear channel configuration */
ctrl_tmp &= ~(MXC_F_ADC_CTRL_ADC_REFSCL | MXC_F_ADC_CTRL_ADC_SCALE | MXC_F_ADC_CTRL_BUF_BYPASS);
/* ADC reference scaling must be set for all channels but two*/
if ((channel != ADC_CH_VDD18) && (channel != ADC_CH_VDD12)) {
ctrl_tmp |= MXC_F_ADC_CTRL_ADC_REFSCL;
}
/* Finalize user-requested channel configuration */
if (adc_scale || channel > ADC_CH_3) {
ctrl_tmp |= MXC_F_ADC_CTRL_ADC_SCALE;
}
if (bypass) {
ctrl_tmp |= MXC_F_ADC_CTRL_BUF_BYPASS;
}
/* Write this configuration */
MXC_ADC->ctrl = ctrl_tmp;
/* Start conversion */
MXC_ADC->ctrl |= MXC_F_ADC_CTRL_CPU_ADC_START;
}
/* ************************************************************************* */
int ADC_GetData(uint16_t *outdata)
{
/* See if a conversion is in process */
if (MXC_ADC->status & MXC_F_ADC_STATUS_ADC_ACTIVE) {
/* Wait for conversion to complete */
while ((MXC_ADC->intr & MXC_F_ADC_INTR_ADC_DONE_IF) == 0);
}
/* Read 32-bit value and truncate to 16-bit for output depending on data align bit*/
if((MXC_ADC->ctrl & MXC_F_ADC_CTRL_ADC_DATAALIGN) == 0)
*outdata = (uint16_t)(MXC_ADC->data); /* LSB justified */
else
*outdata = (uint16_t)(MXC_ADC->data >> 6); /* MSB justified */
/* Check for overflow */
if (MXC_ADC->status & MXC_F_ADC_STATUS_ADC_OVERFLOW) {
return E_OVERFLOW;
}
return E_NO_ERROR;
}
/* ************************************************************************* */
int ADC_SetLimit(mxc_adc_limitsel_t unit, mxc_adc_chsel_t channel,
unsigned int low_enable, unsigned int low_limit,
unsigned int high_enable, unsigned int high_limit)
{
/* Check args */
if ((unit >= ADC_LIMIT_MAX) || (channel >= ADC_CH_MAX))
return E_BAD_PARAM;
/* set channel using the limit */
MXC_ADC->limit[unit] = ((channel << MXC_F_ADC_LIMIT0_CH_SEL_POS) & MXC_F_ADC_LIMIT0_CH_SEL);
/* enable/disable the limit*/
if (low_enable) {
MXC_ADC->limit[unit] |= MXC_F_ADC_LIMIT0_CH_LO_LIMIT_EN |
((low_limit << MXC_F_ADC_LIMIT0_CH_LO_LIMIT_POS) & MXC_F_ADC_LIMIT0_CH_LO_LIMIT);
}
else{
MXC_ADC->limit[unit] &= ~MXC_F_ADC_LIMIT0_CH_LO_LIMIT_EN;
}
if (high_enable) {
MXC_ADC->limit[unit] |= MXC_F_ADC_LIMIT0_CH_HI_LIMIT_EN |
((high_limit << MXC_F_ADC_LIMIT0_CH_HI_LIMIT_POS) & MXC_F_ADC_LIMIT0_CH_HI_LIMIT);
}
else{
MXC_ADC->limit[unit] &= ~MXC_F_ADC_LIMIT0_CH_HI_LIMIT_EN;
}
return E_NO_ERROR;
}
/**@} end of group adc */