Question

using CCS ( code composer stodue )

S4.5) Write C code that uses the SysTick_Wait routine in SysTick.c to wait for 0.25 seconds. (Assume the default 3 MHz clock.) S4.6) Write C code that uses the SysTick_Wait10ms routine in SysTick.c to wait for 0.25 seconds. (Assume the default 3 MHz clock.)

MSP432 P401R

Answer 1

Here is the C code:

#include <stdio.h>
#include "SysTick.h"

int main()
{
SysTick_init ();
  
// On a 3 MHz clock, SysTick_Wait will wait 1/3000000
// which is 333.33333 nanosecs
// 0.25 secs = 2.5 x 10**8 nanosecs
// Parameter to pass is 2.5 x 10**8 / 333.333 = 750,000
SysTick_Wait (750000);
  
// Need to wait 0.25 secs = 250 millisecs
// Since SysTick_Wait10ms waits in multiples of 10 ms, we need to pass 25
SystTick_Wait10ms (25);

return 0;
}