Kinetis SPI at bus clock / 2 not working

キャンセル
次の結果を表示 
表示  限定  | 次の代わりに検索 
もしかして: 

Kinetis SPI at bus clock / 2 not working

772件の閲覧回数
PeterFromSweden
Contributor III

Hi

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

タグ(2)
0 件の賞賛
1 返信

382件の閲覧回数
alejandrolozan1
NXP Employee
NXP Employee

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