Kinetis SPI at bus clock / 2 not working

PeterFromSweden — Thu, 28 Feb 2013 07:15:40 GMT

I am running a K60F120 with a bus clock of 60 MHz. Reference manual ch 3.9.5.2 clearly states that bus clock / 2 is max speed of SPI bus.

The test confirms that the SPI CLK signal is operating at 30 MHz. Thats as expected. But the MISO signal is not perceived correctly by my K60 (master). It seems that the bits are shifted so the physical MSB (first) is received as next bit.

Verification method is by oscilloscope 2 GHz with 1 GHz probes. Curveform looks quite OK.

Is SPI rate = bus clock / 2 really working?

/Peter

Re: Kinetis SPI at bus clock / 2 not working

alejandrolozan1 — Fri, 22 Mar 2013 18:23:46 GMT

Hi,

Can you try to connect the MOSI line with the MISO of the same device?

I mean try to loop back the signal and see that at least you receive what you send correctly.

That would give us a clue if we need to change a parameter.

Regards,

Alejandro

topic Re: Kinetis SPI at bus clock / 2 not working in Kinetis Microcontrollers

Kinetis SPI at bus clock / 2 not working

Re: Kinetis SPI at bus clock / 2 not working