SWD pullups

nickexists · Oct 13, 2015

I am working on making a board that used programming pins instead of an on board boot loader. In this case is it necessary to use pullup resistors and SWD and reset pins, or does the MK20 have it's own pullups?

Frank B · Oct 13, 2015

nickexists said:
I am working on making a board that used programming pins instead of an on board boot loader. In this case is it necessary to use pullup resistors and SWD and reset pins, or does the MK20 have it's own pullups?

Maybe its better to ask the freescale forum...

Constantin · Oct 13, 2015

Frank B said:
Maybe its better to ask the freescale forum...

Or review the schematics to a reference board at Freescale? Presumably they have those listed?

stevech · Oct 13, 2015

SWD interface "pods" I've used take care of all interface aspects. Nothing needed on the board.
Assuming you are using a proper SWD pod.

PaulStoffregen · Oct 13, 2015

The chip has built in pullup and pulldown resistors on those pins. Details are in Freescale's manual.

SWD pullups

nickexists

Active member

Frank B

Senior Member

Constantin

Well-known member

stevech

Well-known member

PaulStoffregen

Well-known member