/* * @brief LPC13xx Chip specific SystemInit * * @note * Copyright(C) NXP Semiconductors, 2013 * 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 ****************************************************************************/ /* Setup system clocking */ void Chip_SetupXtalClocking(void) { volatile int i; /* Powerup main oscillator */ Chip_SYSCTL_PowerUp(SYSCTL_POWERDOWN_SYSOSC_PD); /* Wait an estimated 200us for OSC to be stablized, no status indication, dummy wait */ for (i = 0; i < 0x200; i++) {} /* Set system PLL input to main oscillator */ Chip_Clock_SetSystemPLLSource(SYSCTL_PLLCLKSRC_SYSOSC); /* Power down PLL to change the PLL divider ratio */ Chip_SYSCTL_PowerDown(SYSCTL_POWERDOWN_SYSPLL_PD); /* Setup PLL for main oscillator rate (FCLKIN = 12MHz) * 6 = 72MHz MSEL = 5 (this is pre-decremented), PSEL = 1 (for P = 2) FCLKOUT = FCLKIN * (MSEL + 1) = 12MHz * 6 = 72MHz FCCO = FCLKOUT * 2 * P = 72MHz * 2 * 2 = 288MHz (within FCCO range) */ Chip_Clock_SetupSystemPLL(5, 1); /* Powerup system PLL */ Chip_SYSCTL_PowerUp(SYSCTL_POWERDOWN_SYSPLL_PD); /* Wait for PLL to lock */ while (!Chip_Clock_IsSystemPLLLocked()) {} /* Set system clock divider to 1 */ Chip_Clock_SetSysClockDiv(1); /* Setup FLASH access to 3 clocks (72MHz clock) */ Chip_FMC_SetFLASHAccess(FLASHTIM_72MHZ_CPU); /* Set main clock source to the system PLL. This will drive 72MHz for the main clock and 72MHz for the system clock */ Chip_Clock_SetMainClockSource(SYSCTL_MAINCLKSRC_PLLOUT); } /* Set up and initialize hardware prior to call to main */ void Chip_SetupIrcClocking(void) { /* IRC should be powered up */ Chip_SYSCTL_PowerUp(SYSCTL_POWERDOWN_IRC_PD); Chip_SYSCTL_PowerUp(SYSCTL_POWERDOWN_IRCOUT_PD); /* Set system PLL input to main oscillator */ Chip_Clock_SetSystemPLLSource(SYSCTL_PLLCLKSRC_IRC); /* Power down PLL to change the PLL divider ratio */ Chip_SYSCTL_PowerDown(SYSCTL_POWERDOWN_SYSPLL_PD); /* Setup PLL for main oscillator rate (FCLKIN = 12MHz) * 6 = 72MHz MSEL = 5 (this is pre-decremented), PSEL = 1 (for P = 2) FCLKOUT = FCLKIN * (MSEL + 1) = 12MHz * 6 = 72MHz FCCO = FCLKOUT * 2 * P = 72MHz * 2 * 2 = 288MHz (within FCCO range) */ Chip_Clock_SetupSystemPLL(5, 1); /* Powerup system PLL */ Chip_SYSCTL_PowerUp(SYSCTL_POWERDOWN_SYSPLL_PD); /* Wait for PLL to lock */ while (!Chip_Clock_IsSystemPLLLocked()) {} /* Set system clock divider to 1 */ Chip_Clock_SetSysClockDiv(1); /* Setup FLASH access to 3 clocks */ Chip_FMC_SetFLASHAccess(FLASHTIM_72MHZ_CPU); /* Set main clock source to the system PLL. This will drive 48MHz for the main clock and 48MHz for the system clock */ Chip_Clock_SetMainClockSource(SYSCTL_MAINCLKSRC_PLLOUT); } /* Set up and initialize hardware prior to call to main */ void Chip_SystemInit(void) { /* Initial internal clocking */ Chip_SetupIrcClocking(); }