rockbox/firmware/target/arm/tcc780x/adc-tcc780x.c
Daniel Stenberg 2acc0ac542 Updated our source code header to explicitly mention that we are GPL v2 or
later. We still need to hunt down snippets used that are not. 1324 modified
files...
http://www.rockbox.org/mail/archive/rockbox-dev-archive-2008-06/0060.shtml


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@17847 a1c6a512-1295-4272-9138-f99709370657
2008-06-28 18:10:04 +00:00

108 lines
2.7 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2007 by Dave Chapman
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "config.h"
#include "cpu.h"
#include "system.h"
#include "kernel.h"
#include "thread.h"
#include "string.h"
#include "adc.h"
static unsigned short adcdata[8];
#ifndef BOOTLOADER
/* Tick task */
static void adc_tick(void)
{
int i;
PCLK_ADC |= PCK_EN; /* Enable ADC clock */
/* Start converting the first 4 channels */
for (i = 0; i < 4; i++)
ADCCON = i;
}
/* IRQ handler */
void ADC(void)
{
int num;
uint32_t adc_status;
do
{
adc_status = ADCSTATUS;
num = (adc_status>>24) & 7;
if (num) adcdata[(adc_status >> 16) & 0x7] = adc_status & 0x3ff;
} while (num);
PCLK_ADC &= ~PCK_EN; /* Disable ADC clock */
}
#endif /* BOOTLOADER */
unsigned short adc_read(int channel)
{
#ifdef BOOTLOADER
/* IRQs aren't enabled in the bootloader - just do the read directly */
int i;
uint32_t adc_status;
PCLK_ADC |= PCK_EN; /* Enable ADC clock */
/* Start converting the first 4 channels */
for (i = 0; i < 4; i++)
ADCCON = i;
/* Now read the values back */
for (i=0; i < 4; i++)
{
/* Wait for data to become stable */
while ((ADCDATA & 0x1) == 0);
adc_status = ADCSTATUS;
adcdata[(adc_status >> 16) & 0x7] = adc_status & 0x3ff;
}
PCLK_ADC &= ~PCK_EN; /* Disable ADC clock */
#endif
return adcdata[channel];
}
void adc_init(void)
{
/* consider configuring PCK_ADC source here */
ADCCON = (1<<4); /* Enter standby mode */
ADCCFG |= 0x00000003; /* Single-mode, auto power-down */
#ifndef BOOTLOADER
ADCCFG |= (1<<3); /* Request IRQ on ADC completion */
IEN |= ADC_IRQ_MASK; /* Unmask ADC IRQs */
tick_add_task(adc_tick);
sleep(2); /* Ensure valid readings when adc_init returns */
#endif
}