how to improve S32k3 interrupt callback execute speed?

[Vandarkholme]

hello! I'm migrate project from microchip's PIC series to S32K312.

In PIC chips, set 1us timer -> start timer -> hit timer interrupt  -> toggle pin, can see 1us toggle wave in scope. 

But in S32k3, it's not worked. the minimal toggle time is 6.2us,  I'm confused that why mcu running 120Mhz, but can't interrupt in 1us.

here's scope's 6.2us wave(set pit 1us interrupt) and test project(modified by pit example)

[danielmartynek · Accepted solution]

Hi @Vandarkholme,

Some SW overhead is always expected, but especially with the RTD.

Have a look at Pit_Ip_ProcessCommonInterrupt() in Pit_Ip.c.

This function is called from the PIT interrupt handler before the callback notification is called where you toggle the pin.

Regards,

Daniel