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部件号：MSP432E401Y “线程：测试”中讨论的其它部件
大家好，团队
客户提出的问题可能需要您的帮助：
客户已检查这2个文件：
https://dev.ti.com/tirex/explore/node?node=AOD4LXqFA8XEr21FehvtQA__J4.hfJy__LATEST
https://dev.ti.com/tirex/explore/node?node=AEFKJ9Hm67JXdj9NzpSYFA__J4.hfJy__LATEST&search=432E
并从《技术参考手册》中获得相关说明：
问题在于：重新加注时无法自行设置加注模式。
一些相关信息供参考：
A. 可将倒计数模式设置为10000到0。
B. 代码如下所示。 只需将97行的 TIMER CFG _B_REALARY_TIMER 更改为 TIMER CFG _B_REAL式_UP，并将105行的数据更改为10000，即可轻松观察 LED 的闪烁频率。
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/******************************************************************************
* MSP432E4 Example project for Configuring a timer in 16-bit periodic mode
*
* Description: In this example, the timer is configured to generate an
* interrupt every 0.1 sec in 16-bit periodic mode. On the interrupt the state
* of the LED D2
*
* MSP432E401Y
* ------------------
* /|\| |
* | | |
* --|RST |
* | |
* | PN0|-->LED
* | |
* | |
* | |
* Author: Amit Ashara
*******************************************************************************/
/* DriverLib Includes */
#include <ti/devices/msp432e4/driverlib/driverlib.h>
/* Standard Includes */
#include <stdint.h>
#include <stdbool.h>
void TIMER2B_IRQHandler(void)
{
uint32_t getTimerInterrupt;
/* Get timer interrupt status and clear the same */
getTimerInterrupt = MAP_TimerIntStatus(TIMER2_BASE, true);
MAP_TimerIntClear(TIMER2_BASE, getTimerInterrupt);
/* Toggle the LED */
MAP_GPIOPinWrite(GPIO_PORTN_BASE, GPIO_PIN_0,
~(MAP_GPIOPinRead(GPIO_PORTN_BASE, GPIO_PIN_0)));
}
int main(void)
{
uint32_t systemClock;
/* Configure the system clock for 120 MHz */
systemClock = MAP_SysCtlClockFreqSet((SYSCTL_XTAL_25MHZ | SYSCTL_OSC_MAIN |
SYSCTL_USE_PLL | SYSCTL_CFG_VCO_480),
120000000);
/* Enable the clock to the GPIO Port N and wait for it to be ready */
MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPION);
while(!(SysCtlPeripheralReady(SYSCTL_PERIPH_GPION)))
{
}
/* Configure the GPIO PN0 as output and put in low state */
MAP_GPIOPinTypeGPIOOutput(GPIO_PORTN_BASE, GPIO_PIN_0);
MAP_GPIOPinWrite(GPIO_PORTN_BASE, GPIO_PIN_0, ~(GPIO_PIN_0));
/* Enable the Timer-0 in 16-bit periodic mode with interrupt generated
* every 0.1 sec */
MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_TIMER2);
while(!(SysCtlPeripheralReady(SYSCTL_PERIPH_TIMER2)))
{
}
MAP_TimerConfigure(TIMER2_BASE, TIMER_CFG_SPLIT_PAIR | TIMER_CFG_B_PERIODIC_UP);
MAP_TimerIntEnable(TIMER2_BASE, TIMER_TIMB_TIMEOUT);
/* Since the 16-bit timer can count only 65536 value, we use the pre
* scaler of 256 to divide down the count rate by 256. Thus the actual
* count load is 120e6/256 = 468750. Now when to count at 0.1 sec the
* load value in the timer would be 468750 * 0.1 = 46875 = 0xB71B. */
MAP_TimerPrescaleSet(TIMER2_BASE, TIMER_B, 255);
MAP_TimerLoadSet(TIMER2_BASE, TIMER_B, 10000);
/* Enable Timer Interrupt */
MAP_IntEnable(INT_TIMER2B);
/* Enable the timer count */
MAP_TimerEnable(TIMER2_BASE, TIMER_B);
while(1)
{
}
}
C. 在运行时可以看到上面修改的代码。 当97行参数为 TIMEER_CFG_B_REARISTERY_UP 时，指示灯将快速闪烁，而当它是 TIMEER_CFG_B_B_REPORTY_UP 时，指示灯将不会闪烁。 这不是一个0-10000上下计数，它被称为0-65535。
D. 删除104行且未执行除法时，C 中将不会出现错误。
请帮您检查此案例？ 谢谢。
此致，
樱桃
