1/* 2 * @brief Systick example using systick timer, the SYSTICK clock divider, and the LED 3 * 4 * @note 5 * Copyright(C) NXP Semiconductors, 2013 6 * All rights reserved. 7 * 8 * @par 9 * Software that is described herein is for illustrative purposes only 10 * which provides customers with programming information regarding the 11 * LPC products. This software is supplied "AS IS" without any warranties of 12 * any kind, and NXP Semiconductors and its licensor disclaim any and 13 * all warranties, express or implied, including all implied warranties of 14 * merchantability, fitness for a particular purpose and non-infringement of 15 * intellectual property rights. NXP Semiconductors assumes no responsibility 16 * or liability for the use of the software, conveys no license or rights under any 17 * patent, copyright, mask work right, or any other intellectual property rights in 18 * or to any products. NXP Semiconductors reserves the right to make changes 19 * in the software without notification. NXP Semiconductors also makes no 20 * representation or warranty that such application will be suitable for the 21 * specified use without further testing or modification. 22 * 23 * @par 24 * Permission to use, copy, modify, and distribute this software and its 25 * documentation is hereby granted, under NXP Semiconductors' and its 26 * licensor's relevant copyrights in the software, without fee, provided that it 27 * is used in conjunction with NXP Semiconductors microcontrollers. This 28 * copyright, permission, and disclaimer notice must appear in all copies of 29 * this code. 30 */ 31 32/** @defgroup EXAMPLES_PERIPH_15XX_SYSTICK LPC15xx Simple systick example 33 * @ingroup EXAMPLES_PERIPH_15XX 34 * <b>Example description</b><br> 35 * The Systick example simply blinks an LED at a periodic rate using the systick 36 * timer and SYSTICK clock divider. The LED state is toggled in the systick 37 * interrupt handler.<br> 38 * 39 * <b>NOTE</b><br> 40 * While one would expect a clock divider to delay an interrupt occurrence this implementation 41 * seems to hasten the interrupt occurrence. For example, if the SYSTICK clock divider is set 42 * to 1, 453 interrupts occur in a 30-second interval. If the SYSTICK clock divider is set 43 * to 2, one would expect to see half the interrupt count however twice the interrupts occure as 44 * though the clock divider were really a clock multiplier.<br> 45 * 46 * <b>NOTE</b><br> 47 * In addition, once the SYSTICK clock divider is set and SYSTICK is enabled, the SYSTICK clock 48 * divider becomes static, changes seem to have no effect. Once the clock was running, the effective 49 * rate could not be changed or the SYSTICK timer clock disabled as described in the UM. 50 * 51 * <b>Special connection requirements</b><br> 52 * There are no special connection requirements for this example.<br> 53 * 54 * <b>Build procedures:</b><br> 55 * Visit the <a href="http://www.lpcware.com/content/project/lpcopen-platform-nxp-lpc-microcontrollers/lpcopen-v200-quickstart-guides">LPCOpen quickstart guides</a> 56 * to get started building LPCOpen projects. 57 * 58 * <b>Supported boards and board setup:</b><br> 59 * @ref LPCOPEN_15XX_BOARD_LPCXPRESSO_1549<br> 60 * 61 * <b>Submitting LPCOpen issues:</b><br> 62 * @ref LPCOPEN_COMMUNITY 63 * @{ 64 */ 65 66/** 67 * @} 68 */ 69