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器件型号：LP-MSP430FR2476 主题中讨论的其他器件：MSP-FET、MSP430FR2476
我想使用示例代码"cs_ex1_D3852 1MHz Trim"监视 ACLK、SMCLK 和 MCLK 时钟。
没有时钟波形被输出到相应的引脚"P2.2"、"P1.7"和"P1.3"。
代码已按如下所示进行更改。
#include "driverlib.h"
//*****************************************************************************
//
//Target frequency for MCLK in kHz
//
//*****************************************************************************
#define CS_MCLK_DESIRED_FREQUENCY_IN_KHZ 1000
//*****************************************************************************
//
//MCLK/FLLRef Ratio
//
//*****************************************************************************
#define CS_MCLK_FLLREF_RATIO 30
//*****************************************************************************
//
//Variable to store current Clock values
//
//*****************************************************************************
uint32_t clockValue = 0;
#define GPIO_PORT_MCLK GPIO_PORT_P1
#define GPIO_PIN_MCLK GPIO_PIN3
#define GPIO_FUNCTION_MCLK GPIO_PRIMARY_MODULE_FUNCTION
#define GPIO_PORT_SMCLK GPIO_PORT_P1
#define GPIO_PIN_SMCLK GPIO_PIN7
#define GPIO_FUNCTION_SMCLK GPIO_PRIMARY_MODULE_FUNCTION
#define GPIO_PORT_ACLK GPIO_PORT_P2
#define GPIO_PIN_ACLK GPIO_PIN2
#define GPIO_FUNCTION_ACLK GPIO_PRIMARY_MODULE_FUNCTION
//*****************************************************************************
//
//Variable to store status of Oscillator fault flags
//
//*****************************************************************************
uint16_t status;
void main (void)
{
//Stop watchdog timer
WDT_A_hold(WDT_A_BASE);
GPIO_setAsOutputPin(
GPIO_PORT_P5,
GPIO_PIN0
);
//ACLK set out to pins
GPIO_setAsPeripheralModuleFunctionOutputPin(
GPIO_PORT_ACLK,
GPIO_PIN_ACLK,
GPIO_FUNCTION_ACLK
);
//SMCLK set out to pins
GPIO_setAsPeripheralModuleFunctionOutputPin(
GPIO_PORT_SMCLK,
GPIO_PIN_SMCLK,
GPIO_FUNCTION_SMCLK
);
//MCLK set out to pins
GPIO_setAsPeripheralModuleFunctionOutputPin(
GPIO_PORT_MCLK,
GPIO_PIN_MCLK,
GPIO_FUNCTION_MCLK
);
/*
* Disable the GPIO power-on default high-impedance mode to activate
* previously configured port settings
*/
PMM_unlockLPM5();
//Set DCO FLL reference = REFO
CS_initClockSignal(
CS_FLLREF,
CS_REFOCLK_SELECT,
CS_CLOCK_DIVIDER_1
);
//Set ACLK = REFO
CS_initClockSignal(
CS_ACLK,
CS_REFOCLK_SELECT,
CS_CLOCK_DIVIDER_1
);
//Create struct variable to store proper software trim values
CS_initFLLParam param = {0};
//Set Ratio/Desired MCLK Frequency, initialize DCO, save trim values
CS_initFLLCalculateTrim(
CS_MCLK_DESIRED_FREQUENCY_IN_KHZ,
CS_MCLK_FLLREF_RATIO,
¶m
);
//Clear all OSC fault flag
CS_clearAllOscFlagsWithTimeout(1000);
//For demonstration purpose, change DCO clock freq to 16MHz
CS_initFLLSettle(
16000,
487
);
//Clear all OSC fault flag
CS_clearAllOscFlagsWithTimeout(1000);
//Reload DCO trim values that were calculated earlier
CS_initFLLLoadTrim(
CS_MCLK_DESIRED_FREQUENCY_IN_KHZ,
CS_MCLK_FLLREF_RATIO,
¶m
);
//Clear all OSC fault flag
CS_clearAllOscFlagsWithTimeout(1000);
//Enable oscillator fault interrupt
SFR_enableInterrupt(SFR_OSCILLATOR_FAULT_INTERRUPT);
// Enable global interrupt
__bis_SR_register(GIE);
//Verify if the Clock settings are as expected
clockValue = CS_getSMCLK();
clockValue = CS_getMCLK();
clockValue = CS_getACLK();
while (1)
{
GPIO_toggleOutputOnPin(
GPIO_PORT_P5,
GPIO_PIN3
);
//Delay
__delay_cycles(1000000);
}
}
#if defined(__TI_COMPILER_VERSION__) || defined(__IAR_SYSTEMS_ICC__)
#pragma vector=UNMI_VECTOR
__interrupt
#elif defined(__GNUC__)
__attribute__((interrupt(UNMI_VECTOR)))
#endif
void NMI_ISR(void)
{
do {
// If it still can't clear the oscillator fault flags after the timeout,
// trap and wait here.
status = CS_clearAllOscFlagsWithTimeout(1000);
} while(status != 0);
}
我如何输出内部时钟？
另外、如果我要将内部时钟更改为4MHz、请告诉我要在哪里更改。
谢谢你。
