topic Re: What does pin function name with _b suffix specify? in Kinetis Microcontrollers

What does pin function name with _b suffix specify?

rev — Fri, 09 Oct 2015 15:38:51 GMT

Some Kinetis pin functions have a _b suffix. There's the RESET_b pin, but also others such as UART0_CTS_b.

I've tried searching datasheet and user manual but can't seem to find out what this indicates. Of course there are 100's of matches on _b so I may have missed it.

Re: What does pin function name with _b suffix specify?

mjbcswitzerland — Fri, 09 Oct 2015 15:56:00 GMT

Hi Jonathan

_b means that it is negative logic (eg. RESET_b is reset with a '0', or UART3_RTS_b asserts to '0'). Others will "tend" to be positive logic (asserts to '1' or react to '1' at input).

Regards

Mark

Re: What does pin function name with _b suffix specify?

rev — Fri, 09 Oct 2015 16:27:09 GMT

Ah, of course, silly me! What threw me was that some ADC signals also have a 'b' suffix. Now clearly that means the alternate location since there are ADC signals with 'a' suffix also.

Re: What does pin function name with _b suffix specify?

mjbcswitzerland — Fri, 09 Oct 2015 16:45:07 GMT

Jonathan

Yes, the ADCs have a mux which allows their channel input to be set to either Mux a or Mux b position (although some packages don't support both and in this case there is neither _a nor _b).

Regards

Mark