rt-thread/bsp/lpc824/Libraries/peri_driver/wkt/wkt_8xx.c

82 lines
3.1 KiB
C

/*
* @brief LPC8xx Self Wakeup Timer (WKT) chip driver
*
* @note
* Copyright(C) NXP Semiconductors, 2012
* All rights reserved.
*
* @par
* Software that is described herein is for illustrative purposes only
* which provides customers with programming information regarding the
* LPC products. This software is supplied "AS IS" without any warranties of
* any kind, and NXP Semiconductors and its licensor disclaim any and
* all warranties, express or implied, including all implied warranties of
* merchantability, fitness for a particular purpose and non-infringement of
* intellectual property rights. NXP Semiconductors assumes no responsibility
* or liability for the use of the software, conveys no license or rights under any
* patent, copyright, mask work right, or any other intellectual property rights in
* or to any products. NXP Semiconductors reserves the right to make changes
* in the software without notification. NXP Semiconductors also makes no
* representation or warranty that such application will be suitable for the
* specified use without further testing or modification.
*
* @par
* Permission to use, copy, modify, and distribute this software and its
* documentation is hereby granted, under NXP Semiconductors' and its
* licensor's relevant copyrights in the software, without fee, provided that it
* is used in conjunction with NXP Semiconductors microcontrollers. This
* copyright, permission, and disclaimer notice must appear in all copies of
* this code.
*/
#include "chip.h"
/*****************************************************************************
* Private types/enumerations/variables
****************************************************************************/
/*****************************************************************************
* Public types/enumerations/variables
****************************************************************************/
/*****************************************************************************
* Private functions
****************************************************************************/
/*****************************************************************************
* Public functions
****************************************************************************/
/* Set clock source for WKT */
void Chip_WKT_SetClockSource(LPC_WKT_T *pWKT, WKT_CLKSRC_T clkSrc)
{
if (clkSrc == WKT_CLKSRC_10KHZ) {
pWKT->CTRL |= WKT_CTRL_CLKSEL; /* using Low Power clock 10kHz */
}
else {
pWKT->CTRL &= ~WKT_CTRL_CLKSEL; /* using Divided IRC clock 750kHz */
}
}
/* Return approximate rate for the selected clock source */
uint32_t Chip_WKT_GetClockRate(LPC_WKT_T *pWKT)
{
if (Chip_WKT_GetClockSource(pWKT) == WKT_CLKSRC_DIVIRC) {
/* Approximately 750KHz */
return (750 * 1000);
}
else {
/* Approximately 10KHz */
return (10 * 1000);
}
}
/* Start wake-up timer interrupt, set clock source, set timer interval */
void Chip_WKT_Start(LPC_WKT_T *pWKT, WKT_CLKSRC_T clkSrc, uint32_t cntVal)
{
/* Set the WKT clock source */
Chip_WKT_SetClockSource(pWKT, (WKT_CLKSRC_T) clkSrc);
/* Set the WKT counter & start it */
pWKT->COUNT = cntVal;
}