1 /*
2  * @brief CLKOUT example
3  *
4  * @note
5  * Copyright(C) NXP Semiconductors, 2014
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 "board.h"
33 #include <stdio.h>
34 
35 /*****************************************************************************
36  * Private types/enumerations/variables
37  ****************************************************************************/
38 
39 static volatile uint32_t ticks100;
40 
41 #if defined(BOARD_NXP_LPCXPRESSO_1549)
42 /* Use this pin for clockout */
43 #define CLKOUT_PORT 1
44 #define CLKOUT_PIN  0
45 
46 #else
47 #error "No port/pin defined for the LPC15xx CLKOUT example"
48 #endif
49 
50 /*****************************************************************************
51  * Public types/enumerations/variables
52  ****************************************************************************/
53 
54 /*****************************************************************************
55  * Private functions
56  ****************************************************************************/
57 
58 /*****************************************************************************
59  * Public functions
60  ****************************************************************************/
61 
62 /**
63  * @brief	Handle interrupt from SysTick timer
64  * @return	Nothing
65  */
SysTick_Handler(void)66 void SysTick_Handler(void)
67 {
68 	ticks100++;
69 	if ((ticks100 % 100) == 0) {
70 		Board_LED_Toggle(0);
71 	}
72 }
73 
74 /**
75  * @brief	main routine for CLKOUT example
76  * @return	Function should not exit.
77  */
main(void)78 int main(void)
79 {
80 	CHIP_SYSCTL_CLKOUTSRC_T clkoutClks;
81 
82 	SystemCoreClockUpdate();
83 	Board_Init();
84 
85 	Board_LED_Set(0, false);
86 
87 	/* Enable and setup SysTick Timer at a 100Hz rate */
88 	SysTick_Config(Chip_Clock_GetSysTickClockRate() / 100);
89 
90 	/* Enable the power to the WDT */
91 	Chip_SYSCTL_PowerUp(SYSCTL_POWERDOWN_WDTOSC_PD);
92 	/* Setup SCT PLL */
93 	Chip_SYSCTL_PowerDown(SYSCTL_POWERDOWN_SCTPLL_PD);
94 	Chip_Clock_SetSCTPLLSource(SYSCTL_PLLCLKSRC_MAINOSC);
95 	Chip_Clock_SetupSCTPLL(5, 2);
96 	Chip_SYSCTL_PowerUp(SYSCTL_POWERDOWN_SCTPLL_PD);
97 	/* Wait for PLL to lock */
98 	while (!Chip_Clock_IsSCTPLLLocked()) {}
99 	/* Enable RTC Oscillator */
100 	Chip_Clock_EnableRTCOsc();
101 
102 	/* Enable SWM clocking prior to switch matrix operations */
103 	Chip_SWM_Init();
104 	Chip_GPIO_Init(LPC_GPIO);
105 
106 	/* Setup pin as CLKOUT */
107 	Chip_SWM_MovablePortPinAssign(SWM_CLK_OUT_O, CLKOUT_PORT, CLKOUT_PIN);
108 
109 	/* Configure as a digital pin with no pullups/pulldowns */
110 	Chip_IOCON_PinMuxSet(LPC_IOCON, CLKOUT_PORT, CLKOUT_PIN,
111 						 (IOCON_MODE_INACT | IOCON_DIGMODE_EN));
112 
113 	/* Cycle through all clock sources for the CLKOUT pin */
114 	while (1) {
115 		for (clkoutClks = SYSCTL_CLKOUTSRC_IRC;
116 			 clkoutClks <= SYSCTL_CLKOUTSRC_RTC32K; clkoutClks++) {
117 
118 			/* Setup CLKOUT pin for specific clock with a divider of 1 */
119 			Chip_Clock_SetCLKOUTSource(clkoutClks, 1);
120 
121 			/* Wait 5 seconds */
122 			ticks100 = 0;
123 			while (ticks100 < 500) {
124 				__WFI();
125 			}
126 		}
127 	}
128 
129 	/* Disable CLKOUT pin by setting divider to 0 */
130 	Chip_Clock_SetCLKOUTSource(SYSCTL_CLKOUTSRC_MAINSYSCLK, 0);
131 
132 	return 0;
133 }
134