Marco Menchise

MCF52235 GPIO and core synchronization

Discussion created by Marco Menchise on May 8, 2008
Latest reply on May 20, 2008 by Bryan Kattwinkel
Hello,
I'm trying to use a MCF52235 GPIO to output a digital waveform. It is clocked by a 25 MHz oscillator, and PLL is configured to produce a system clock of 60 MHz.

I discovered that I cannot generate precise pulses: the duration of the pulse is random even if I use assembler and TRAPF instructions to control it.

If I try to generate a pulse 500 ns long, for example, I get a pulse log 500+- 32ns, randomly.

Could someone please explain this? Is there an absolute maximum in the random component?

Thanks,
Marco


Message Edited by ariaveta on 2008-05-08 11:32 PM

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