S32K144 GPO Output pulse is different from Simulink scope

HyeonJun94 — Wed, 28 May 2025 07:27:26 GMT

Hello everyone

I’m trying to generate an engine crank signal using two GPOs of the S32K144 EVB via Simulink. The signal has 60 teeth with 2 missing teeth, and during the missing teeth section, one of the GPO outputs is held high (1) while the other is held low (0) to represent an intermediate 'idle' state.

In the attached Simulink model, when I observe the combined waveforms using a Scope block, the output appears as a clean square waveform, and the idle section is clearly and correctly shown.

However, when I implement this on the actual S32K144 EVB, I connect each GPO output through a 1k Ohm resistor and combine them to observe the waveform on an oscilloscope. In this case, I notice that the idle state appears very briefly between every pulse, not just at the missing teeth section.

I’m wondering why there is a discrepancy between the Scope output in Simulink and the actual waveform from the hardware. Could this be due to a mistake in my hardware setup or Simulink configuration? I would appreciate any guidance or suggestions.

Thank you!

topic S32K144 GPO Output pulse is different from Simulink scope in Model-Based Design Toolbox (MBDT)

S32K144 GPO Output pulse is different from Simulink scope