新手求助，怎么用TTIMERA和TIMERB同时测量上升沿和下降沿啊

iot_

想用TIMER0来测量高电平的持续时间，现在能读出TIMERA上升沿的定时器数值，却读不出来TIMERB下降沿定时器数值，，求大家帮帮我，，谢谢大家了
楼主程序
#include
#include
#include "inc/tm4c123gh6pm.h"
#include "inc/hw_memmap.h"
#include "inc/hw_types.h"
#include "driverlib/pin_map.h"
#include "driverlib/sysctl.h"
#include "driverlib/interrupt.h"
#include "driverlib/gpio.h"
#include "driverlib/timer.h"
#define GPIO_PB6_T0CCP0         0x00011807
float time,time1;
int main(void)
{
    SysCtlClockSet(SYSCTL_SYSDIV_5|SYSCTL_USE_PLL|SYSCTL_XTAL_16MHZ|SYSCTL_OSC_MAIN);
    //5分频，使用PLL，外部晶振16M，system时钟源选择 main osc。系统时钟40MHZ
    SysCtlPeripheralEnable(SYSCTL_PERIPH_TIMER0);
        //使能TIMER0 32位(TIMER0A16位+TIMER0B16位)
    SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOF);
   // SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOB);
    //使能GPIOF和GPIOC外设
  //  GPIOPinTypeGPIOOutput(GPIO_PORTF_BASE, GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_3);
    GPIOPinTypeGPIOInput(GPIO_PORTB_BASE, GPIO_PIN_6);
    GPIOPinConfigure(GPIO_PB6_T0CCP0);    //#define GPIO_PC4_WT0CCP0   0x00021007
    GPIOPinTypeTimer(GPIO_PORTB_BASE, GPIO_PIN_6);

    TimerConfigure(TIMER0_BASE,TIMER_CFG_A_CAP_TIME_UP|TIMER_CFG_SPLIT_PAIR);//计时捕获模式，上升沿捕获
    TimerConfigure(TIMER0_BASE,TIMER_CFG_B_CAP_TIME_UP|TIMER_CFG_SPLIT_PAIR);

    TimerControlEvent(TIMER0_BASE,TIMER_A,TIMER_EVENT_POS_EDGE);
    TimerControlEvent(TIMER0_BASE,TIMER_B,TIMER_EVENT_NEG_EDGE);

    IntEnable(INT_TIMER0A);
      IntEnable(INT_TIMER0B);

    //使能TIMER0A
    TimerIntEnable(TIMER0_BASE, TIMER_CAPA_EVENT);
    TimerIntEnable(TIMER0_BASE, TIMER_CAPB_EVENT);

    IntMasterEnable();
    //master interrupt enable API for all interrupts
    TimerEnable(TIMER0_BASE, TIMER_BOTH);

    while(1)
    {
    }
}

void Timer0IntHandler(void)
{


    TimerIntClear(TIMER0_BASE,TIMER_CAPA_EVENT);
    time=TimerValueGet(TIMER0_BASE,TIMER_A) ;


}
void Timer1IntHandler(void)
{


    TimerIntClear(TIMER0_BASE,TIMER_CAPB_EVENT);
    time1=TimerValueGet(TIMER0_BASE,TIMER_B) ;


}

iot_

有木有测量一个引脚的高电平时间的函数的程序啊，，