topic Re: Getting SPI MISO logic level,really need to switch in GPIO? in Kinetis Microcontrollers

Getting SPI MISO logic level,really need to switch in GPIO?

diegocolombo — Fri, 07 Feb 2014 08:08:42 GMT

What should i expect if i read the logic level of MISO pin by the PDIR register (GPIOx_PDIR & 0xx),unless the MUX is switched to GPIO from SPI_MISO alternate function?

Thanks.

Re: Getting SPI MISO logic level,really need to switch in GPIO?

kerryzhou — Sat, 08 Feb 2014 05:50:11 GMT

Hi Diego Colombo,

I don't know which chip you are used, but as I know, our Kinetis K ,KL, KE chip all has the funtion which you need. It is when you configure the pin to other function, not the GPIO function,

you still can read the GPIOx_PDIR to get the pin logic value.

Actually, in the chapter GPIO of our reference manual, it has detail description like the following:

So, if you use the Kinetis K ,KL, KE chip, you don't need to switch to GPIO, just read it directly! I already verify it successfully!

Wish my answer is useful to you!

Best regards!

Jingjing

Re: Getting SPI MISO logic level,really need to switch in GPIO?

diegocolombo — Tue, 11 Feb 2014 10:56:17 GMT

Many thanks Jingjining,thanks for hightlighting the part that i missed to notice reading the datasheet

Forgive me if i did't mention what uC i was talking of,

it is about KL series

Have a good day!

Diego