LPCOpen Platform for LPC112X microcontrollers  112X
LPCOpen Platform for the NXP LPC112X family of Microcontrollers
sysinit_112x.c
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1 /*
2  * @brief LPC11xx Chip specific SystemInit
3  *
4  * @note
5  * Copyright(C) NXP Semiconductors, 2012
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 #include "chip.h"
33 
34 /*****************************************************************************
35  * Private types/enumerations/variables
36  ****************************************************************************/
37 
38 /*****************************************************************************
39  * Public types/enumerations/variables
40  ****************************************************************************/
41 
42 /*****************************************************************************
43  * Private functions
44  ****************************************************************************/
45 
46 /*****************************************************************************
47  * Public functions
48  ****************************************************************************/
49 
50 /* Setup system clocking */
52 {
53  volatile int i;
54 
55  /* Powerup main oscillator */
57 
58  /* Wait 200us for OSC to be stablized, no status
59  indication, dummy wait. */
60  for (i = 0; i < 0x200; i++) {}
61 
62  /* Set system PLL input to main oscillator */
64 
65  /* Power down PLL to change the PLL divider ratio */
67 
68  /* Setup PLL for main oscillator rate (FCLKIN = 12MHz) * 4 = 48MHz
69  MSEL = 3 (this is pre-decremented), PSEL = 1 (for P = 2)
70  FCLKOUT = FCLKIN * (MSEL + 1) = 12MHz * 4 = 48MHz
71  FCCO = FCLKOUT * 2 * P = 48MHz * 2 * 2 = 192MHz (within FCCO range) */
73 
74  /* Powerup system PLL */
76 
77  /* Wait for PLL to lock */
78  while (!Chip_Clock_IsSystemPLLLocked()) {}
79 
80  /* Set system clock divider to 1 */
82 
83  /* Setup FLASH access to 3 clocks */
85 
86  /* Set main clock source to the system PLL. This will drive 48MHz
87  for the main clock and 48MHz for the system clock */
89 }
90 
91 /* Set up and initialize clocking prior to call to main */
93 {
94  /* IRC should be powered up */
97 
98  /* Set system PLL input to main oscillator */
100 
101  /* Power down PLL to change the PLL divider ratio */
103 
104  /* Setup PLL for main oscillator rate (FCLKIN = 12MHz) * 4 = 48MHz
105  MSEL = 3 (this is pre-decremented), PSEL = 1 (for P = 2)
106  FCLKOUT = FCLKIN * (MSEL + 1) = 12MHz * 4 = 48MHz
107  FCCO = FCLKOUT * 2 * P = 48MHz * 2 * 2 = 192MHz (within FCCO range) */
109 
110  /* Powerup system PLL */
112 
113  /* Wait for PLL to lock */
114  while (!Chip_Clock_IsSystemPLLLocked()) {}
115 
116  /* Set system clock divider to 1 */
118 
119  /* Setup FLASH access to 3 clocks */
121 
122  /* Set main clock source to the system PLL. This will drive 48MHz
123  for the main clock and 48MHz for the system clock */
125 
126  /* Enable IOCON clock */
128 }
129 
130 /* Set up and initialize hardware prior to call to main */
131 void Chip_SystemInit(void)
132 {
133  /* Initial internal clocking */
135 }