MSP432E401Y: TIMER Inquiry

Part Number: MSP432E401Y

Hi,

Good day. Our customer has an inquiry about the MSP432E4's timer. Kindly see below.

There is a question about MSP432E4's Timer, 16-bits used individually,I can configure Timer2B as TIMER_CFG_B_PERIODIC, and use MAP_TimerLoadSet set the counter to 1000, it may count from 1000 to 0,that's all right

if I change TIMER_CFG_B_PERIODIC by TIMER_CFG_B_PERIODIC_UP it could not work, only 0-65535.

No error encountered. I want count up from 0-load(match)

https://paste.ubuntu.com/p/pYN2Zw4k9T/

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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

/* Standard Includes */
#include
#include
#include "uartstdio.h"
int i=0;
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 */
if(1)
{
i=0;
MAP_GPIOPinWrite(GPIO_PORTN_BASE, GPIO_PIN_0,
~(MAP_GPIOPinRead(GPIO_PORTN_BASE, GPIO_PIN_0)));
UARTprintf("cnt\r\n");
}
}

void ConfigureUART(uint32_t systemClock)
{
/* Enable the clock to GPIO port A and UART 0 */
MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOA);
MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_UART0);

/* Configure the GPIO Port A for UART 0 */
MAP_GPIOPinConfigure(GPIO_PA0_U0RX);
MAP_GPIOPinConfigure(GPIO_PA1_U0TX);
MAP_GPIOPinTypeUART(GPIO_PORTA_BASE, GPIO_PIN_0 | GPIO_PIN_1);

/* Configure the UART for 115200 bps 8-N-1 format */
UARTStdioConfig(0, 115200, systemClock);
}

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);

ConfigureUART(systemClock);
/* 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);/*TIMER_CFG_B_PERIODIC work*/
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, (systemClock/(256*10)));

// MAP_TimerLoadSet(TIMER2_BASE, TIMER_B, 10000); /*could not work,just count 0-65535*/
// MAP_TimerMatchSet(TIMER2_BASE, TIMER_B, 10000); /*could not work,just count 0-65535*/

//MAP_TimerMatchSet(TIMER2_BASE, TIMER_B, (systemClock/(256*10)));

/* Enable Timer Interrupt */
MAP_IntEnable(INT_TIMER2B);

/* Enable the timer count */
MAP_TimerEnable(TIMER2_BASE, TIMER_B);
UARTprintf("Hello\r\n");
while(1)
{
}
}