SysTickPeriodicInt

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This is a C language project that implements periodic interrupts using SysTick. The red LCD (PA0) on the LaunchPad toggles within the SysTick ISR.
 
In the following figure, PB27 is toggled within the SysTick ISR, showing the interrupt period is 1ms. PA0 is toggled in the main program, so at this scale, PA0 toggles faster than can be captured.

Next figure shows the same two signals zoomed in. The overall activity is PA0 toggling, ISR is invoked, PB27 is toggled in the ISR, the main program is resumed, and the toggling on PA0 continues. The recording shows the entire ISR consumed about 1.5us to process.

Hardware Required

  • MSPM0G3507 LaunchPad™ Development Kit (LP-MSPM0G3507)
Pin assignments
  • Output: PA0 is red LED1, index 0 in IOMUX PINCM table
LaunchPad Jumpers
  • J5: Connects PB22 to blue LED2
  • J6: Connects PB26 to red LED2
  • J7: Connects PB27 to green LED2

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