Diff: TIMER/FreqMeasure/freqmeasure.c

Revision:

0:bf7b9fba3924

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TIMER/FreqMeasure/freqmeasure.c	Sun Mar 20 05:38:56 2011 +0000
@@ -0,0 +1,244 @@
+/******************** (C) COPYRIGHT 2010 NXPSemiconductors ************
+ * @file		freqmeasure.c
+ * @purpose		This example describes how to use TIMER capture function
+ * @version		1.0
+ * @date		16. July. 2010
+ * @author		NXP MCU SW Application Team
+ *---------------------------------------------------------------------
+ * Software that is described herein is for illustrative purposes only
+ * which provides customers with programming information regarding the
+ * products. This software is supplied "AS IS" without any warranties.
+ * NXP Semiconductors assumes no responsibility or liability for the
+ * use of the software, conveys no license or title under any patent,
+ * copyright, or mask work right to the product. NXP Semiconductors
+ * reserves the right to make changes in the software without
+ * notification. NXP Semiconductors also make no representation or
+ * warranty that such application will be suitable for the specified
+ * use without further testing or modification.
+ **********************************************************************/
+#include "lpc17xx_timer.h"
+#include "lpc17xx_libcfg.h"
+#include "lpc17xx_pinsel.h"
+#include "debug_frmwrk.h"
+
+
+/* Example group ----------------------------------------------------------- */
+/** @defgroup TIMER_FreqMeasure		FreqMeasure
+ * @ingroup TIMER_Examples
+ * @{
+ */
+
+/************************** PRIVATE VARIABLES *************************/
+uint8_t menu1[] =
+"********************************************************************************\n\r"
+"Hello NXP Semiconductors \n\r"
+"Timer measure frequency demo \n\r"
+"\t - MCU: LPC17xx \n\r"
+"\t - Core: ARM Cortex-M3 \n\r"
+"\t - Communicate via: UART0 -  115200 bps \n\r"
+" Use timer 0 to measure input signal frequency through its CAP0.0 \n\r"
+" Use timer 2 to generate different frequency signals \n\r"
+"********************************************************************************\n\r";
+
+TIM_TIMERCFG_Type TIM_ConfigStruct;
+TIM_CAPTURECFG_Type TIM_CaptureConfigStruct;
+
+BOOL_8 first_capture,done;
+uint32_t capture;
+uint8_t count=0;
+/************************** PRIVATE FUNCTIONS *************************/
+/* Interrupt service routines */
+void TIMER0_IRQHandler(void);
+
+void print_menu(void);
+/*----------------- INTERRUPT SERVICE ROUTINES --------------------------*/
+/*********************************************************************//**
+ * @brief		TIMER0 interrupt handler sub-routine
+ * @param[in]	None
+ * @return 		None
+ **********************************************************************/
+void TIMER0_IRQHandler(void)
+{
+	if (TIM_GetIntCaptureStatus(LPC_TIM0,0))
+	{
+		TIM_ClearIntCapturePending(LPC_TIM0,0);
+		if(first_capture==TRUE)
+		{
+			TIM_Cmd(LPC_TIM0,DISABLE);
+			TIM_ResetCounter(LPC_TIM0);
+			TIM_Cmd(LPC_TIM0,ENABLE);
+			count++;
+			if(count==5)first_capture=FALSE; //stable
+		}
+		else
+		{
+			count=0; //reset count for next use
+			done=TRUE;
+			capture = TIM_GetCaptureValue(LPC_TIM0,0);
+		}
+	}
+}
+
+/*-------------------------PRIVATE FUNCTIONS------------------------------*/
+/*********************************************************************//**
+ * @brief		Print menu
+ * @param[in]	None
+ * @return 		None
+ **********************************************************************/
+void print_menu(void)
+{
+	_DBG(menu1);
+}
+
+
+/*-------------------------MAIN FUNCTION------------------------------*/
+/*********************************************************************//**
+ * @brief		c_entry: Main TIMER program body
+ * @param[in]	None
+ * @return 		int
+ **********************************************************************/
+int c_entry(void)
+{
+	PINSEL_CFG_Type PinCfg;
+	TIM_MATCHCFG_Type TIM_MatchConfigStruct;
+	uint8_t idx;
+	uint16_t tem;
+	uint32_t freq,temcap;
+	/* Initialize debug via UART0
+	 * – 115200bps
+	 * – 8 data bit
+	 * – No parity
+	 * – 1 stop bit
+	 * – No flow control
+	 */
+	debug_frmwrk_init();
+
+	// print welcome screen
+	print_menu();
+
+
+	//Config P1.26 as CAP0.0
+	PinCfg.Funcnum = 3;
+	PinCfg.OpenDrain = 0;
+	PinCfg.Pinmode = 0;
+	PinCfg.Portnum = 1;
+	PinCfg.Pinnum = 26;
+	PINSEL_ConfigPin(&PinCfg);
+	// Configure P0.6 as MAT2.0
+	PinCfg.Funcnum = 3;
+	PinCfg.OpenDrain = 0;
+	PinCfg.Pinmode = 0;
+	PinCfg.Portnum = 0;
+	PinCfg.Pinnum = 6;
+	PINSEL_ConfigPin(&PinCfg);
+
+	while(1)
+	{
+		// Initialize timer 0, prescale count time of 1uS
+		TIM_ConfigStruct.PrescaleOption = TIM_PRESCALE_USVAL;
+		TIM_ConfigStruct.PrescaleValue	= 1;
+
+		// use channel 0, CAPn.0
+		TIM_CaptureConfigStruct.CaptureChannel = 0;
+		// Enable capture on CAPn.0 rising edge
+		TIM_CaptureConfigStruct.RisingEdge = ENABLE;
+		// Enable capture on CAPn.0 falling edge
+		TIM_CaptureConfigStruct.FallingEdge = DISABLE;
+		// Generate capture interrupt
+		TIM_CaptureConfigStruct.IntOnCaption = ENABLE;
+
+		// Set configuration for Tim_config and Tim_MatchConfig
+		TIM_Init(LPC_TIM0, TIM_TIMER_MODE,&TIM_ConfigStruct);
+		TIM_ConfigCapture(LPC_TIM0, &TIM_CaptureConfigStruct);
+		TIM_ResetCounter(LPC_TIM0);
+	///////////////////////////////////////////////////////////////////
+		idx=0;freq=0;tem=0;
+		while(idx<3)
+		{
+			if(idx==0)
+			_DBG("\n\rPlease input frequency (from 1 to 999 hz):");
+			tem = _DG;
+			switch(tem)
+			{
+			case '0':case'1':case '2':case '3':case '4':case '5':case '6':case '7':case'8':case '9':
+				tem = tem - 0x30;
+				idx++;
+				if(idx==1) tem = tem * 100;
+				else if (idx==2) tem = tem * 10;
+				freq = freq + tem;
+				if(idx==3)_DBD16(freq);
+				tem = 0;
+				break;
+			default:
+				_DBG("...Please input digits from 0 to 9 only!");
+				idx = 0; tem = 0; freq = 0;
+				break;
+			}
+		}
+		TIM_ConfigStruct.PrescaleOption = TIM_PRESCALE_USVAL;
+		TIM_ConfigStruct.PrescaleValue	= 1;//1us
+		TIM_Init(LPC_TIM2, TIM_TIMER_MODE,&TIM_ConfigStruct);
+
+		// use channel 0, MR0
+		TIM_MatchConfigStruct.MatchChannel = 0;
+		// Disable interrupt when MR0 matches the value in TC register
+		TIM_MatchConfigStruct.IntOnMatch   = FALSE;
+		//Enable reset on MR0: TIMER will reset if MR0 matches it
+		TIM_MatchConfigStruct.ResetOnMatch = TRUE;
+		//Stop on MR0 if MR0 matches it
+		TIM_MatchConfigStruct.StopOnMatch  = FALSE;
+		//Toggle MR0.0 pin if MR0 matches it
+		TIM_MatchConfigStruct.ExtMatchOutputType =TIM_EXTMATCH_TOGGLE;
+		// Set Match value
+		TIM_MatchConfigStruct.MatchValue   = 500000/freq;
+		TIM_ConfigMatch(LPC_TIM2,&TIM_MatchConfigStruct);
+
+		TIM_Cmd(LPC_TIM2,ENABLE);
+	//////////////////////////////////////////////////////////////////
+		/* preemption = 1, sub-priority = 1 */
+		NVIC_SetPriority(TIMER0_IRQn, ((0x01<<3)|0x01));
+		/* Enable interrupt for timer 0 */
+		NVIC_EnableIRQ(TIMER0_IRQn);
+
+		first_capture = TRUE;done=FALSE;capture=0;
+		// To start timer 0
+		TIM_Cmd(LPC_TIM0,ENABLE);
+
+		_DBG("\n\rMeasuring......");
+		while(done==FALSE);
+		temcap = 1000000 / capture;_DBD16(temcap);_DBG("hz");
+		NVIC_DisableIRQ(TIMER0_IRQn);
+		TIM_DeInit(LPC_TIM0);
+		TIM_DeInit(LPC_TIM2);
+		_DBG("\n\rPress c to continue measuring other signals...");
+		while(_DG != 'c');
+	}
+	while (1);
+	return 1;
+}
+
+/* Support required entry point for other toolchain */
+int main (void)
+{
+	return c_entry();
+}
+#ifdef  DEBUG
+/*******************************************************************************
+* @brief		Reports the name of the source file and the source line number
+* 				where the CHECK_PARAM error has occurred.
+* @param[in]	file Pointer to the source file name
+* @param[in]    line assert_param error line source number
+* @return		None
+*******************************************************************************/
+void check_failed(uint8_t *file, uint32_t line)
+{
+	/* User can add his own implementation to report the file name and line number,
+	 ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
+
+	/* Infinite loop */
+	while(1);
+}
+#endif
+/*
+ * @}
+ */