1 /*
2 ** ###################################################################
3 **     Processors:          LPC804M101JDH20
4 **                          LPC804M101JDH24
5 **                          LPC804M101JHI33
6 **                          LPC804M111JDH24
7 **                          LPC804UK
8 **
9 **     Compilers:           GNU C Compiler
10 **                          IAR ANSI C/C++ Compiler for ARM
11 **                          Keil ARM C/C++ Compiler
12 **                          MCUXpresso Compiler
13 **
14 **     Reference manual:    LPC804 User manual Rev.1.0  24 Jan 2018
15 **     Version:             rev. 1.0, 2018-01-09
16 **     Build:               b201015
17 **
18 **     Abstract:
19 **         Provides a system configuration function and a global variable that
20 **         contains the system frequency. It configures the device and initializes
21 **         the oscillator (PLL) that is part of the microcontroller device.
22 **
23 **     Copyright 2016 Freescale Semiconductor, Inc.
24 **     Copyright 2016-2020 NXP
25 **     All rights reserved.
26 **
27 **     SPDX-License-Identifier: BSD-3-Clause
28 **
29 **     http:                 www.nxp.com
30 **     mail:                 support@nxp.com
31 **
32 **     Revisions:
33 **     - rev. 1.0 (2018-01-09)
34 **         Initial version.
35 **
36 ** ###################################################################
37 */
38 
39 /*!
40  * @file LPC804
41  * @version 1.0
42  * @date 2018-01-09
43  * @brief Device specific configuration file for LPC804 (implementation file)
44  *
45  * Provides a system configuration function and a global variable that contains
46  * the system frequency. It configures the device and initializes the oscillator
47  * (PLL) that is part of the microcontroller device.
48  */
49 
50 #include <stdint.h>
51 #include "fsl_device_registers.h"
52 
53 
54 
55 
56 
57 /* ----------------------------------------------------------------------------
58    -- Core clock
59    ---------------------------------------------------------------------------- */
60 
61 uint32_t SystemCoreClock = DEFAULT_SYSTEM_CLOCK;
62 
63 /* ----------------------------------------------------------------------------
64    -- SystemInit()
65    ---------------------------------------------------------------------------- */
66 
SystemInit(void)67 void SystemInit (void) {
68 
69 #if defined(__MCUXPRESSO)
70     extern void(*const g_pfnVectors[]) (void);
71     SCB->VTOR = (uint32_t) &g_pfnVectors;
72 #else
73     extern void *__Vectors;
74     SCB->VTOR = (uint32_t) &__Vectors;
75 #endif
76     SystemCoreClock = DEFAULT_SYSTEM_CLOCK;
77   SystemInitHook();
78 }
79 
80 /* ----------------------------------------------------------------------------
81    -- SystemCoreClockUpdate()
82    ---------------------------------------------------------------------------- */
83 
SystemCoreClockUpdate(void)84 void SystemCoreClockUpdate (void) {
85 
86 
87     switch (SYSCON->MAINCLKSEL & SYSCON_MAINCLKSEL_SEL_MASK)
88     {
89         case 0U: /* Free running oscillator (FRO / 2) */
90             SystemCoreClock = (g_Fro_Osc_Freq >> 1U);
91             break;
92         case 1U: /* System oscillator */
93             SystemCoreClock = CLK_OSC_IN;
94             break;
95         case 2U: /* lower power oscillator */
96             SystemCoreClock = CLK_OSC_LP;
97             break;
98         case 3U: /* Free running oscillator ((FRO / 2) / 2) */
99             SystemCoreClock = (g_Fro_Osc_Freq >> 2U);
100             break;
101         default:
102             SystemCoreClock = 0U;
103             break;
104     }
105 
106   SystemCoreClock /= SYSCON->SYSAHBCLKDIV;
107 }
108 
109 /* ----------------------------------------------------------------------------
110    -- SystemInitHook()
111    ---------------------------------------------------------------------------- */
112 
SystemInitHook(void)113 __attribute__ ((weak)) void SystemInitHook (void) {
114   /* Void implementation of the weak function. */
115 }
116