Common GPIO Problem

Greetings Sue,

Always glad to see & read (so instructive) your posts.  Thank you - appreciated.

Clearly what you say makes great sense - but does this sole (bit cryptic) forum reference fully/properly, "deal with this (pardon)  long, underserved issue?"

My small group often works in defense and medical - what we note is most all such, "proven gotchas" receive the benefit of, "front of the manual, boldface/highlighting!"  And - the warnings/alerts appear "front/center" of each appropriate chapter w/in the product's manual/brief.  (again - with their title emboldened)

Surely you - many experienced users - may guess the meaning of, "common GPIO problems."  That said - would not an alternate title bear some consideration?  (i.e. "Certain GPIO fail to respond - even after careful, GPIO library-compliant, programming - which works well w/all other GPIO!") 

So many - for so long - have "missed" the current MCU advisory!  (too passive, non highlighted)   While this is a, "Sue C. post" (and a sticky at that) might it also be in need of greater definition (i.e. more precise title) and the accompaniment of boldface type - multiple places - w/in MCU manuals - so that still more user/clients do not land upon such rough/rocky/unexpected, "NMI" shores?

Sue Cozart said:

 A software example to follow to change the function of these pins can be found in the gpio_jtag example that is in all board software packages.

 Hi Sue, concise and simple, well done I like very much but a flaw: Jtag example explain how to use JTAG pin as GPIO, no guide is on place for Port D/E F to unlock from NMI default. I think Just few word can  be added in term of example or better a special Example "port lock/unlock" as simple as possible added to tivaware on your best feel.

Hi Roberto,

Thank you for your comments.  You are correct that the gpio_jtag doesn't include software for the NMI pins, but it can easily be modified to work for the NMI pins. As far as the idea of a specific API for the function goes, long ago the team decided not to create an API for it to reduce the chance of it getting accidentally called and disabling the JTAG interface.

Regards,

Sue

Sue Cozart said:

ou are correct that the gpio_jtag doesn't include software for the NMI pins, but it can easily be modified to work for the NMI pins.

 Hi Sue, thank for kind answer, I appreciate, I learnt about NMI in silence when I early adopted new TIVA series aka Stellaris LM4F120, after that I am aware about, my point is to broad noise is on forum and NMI lock failure repeat too often.

Roberto Romano said:

special Example "port lock/unlock" as simple as possible added to tivaware on your best feel

A code snippet for "unlock from NMI default", can be found at Tivaware ButtonsInit(), which, can be found at "ek-tm4c123gxl\drivers\buttons.c".

Also, "Unlock from NMI default", has been documented at laboratory workshop pdf.

- kel

Markel Robregado said:

A code snippet for "unlock from NMI default", can be found at Tivaware ButtonsInit(), which, can be found at "ek-tm4c123gxl\drivers\buttons.c".

 Dear Markel, I see this appear from your signature a singular todo...

 The example you are speaking about when I was beginner sounded so harsh I simply trashed it. Again I tryid to use to make a Paper tape reader simulator and AGAIN I trashed out both LED driver and Push button too... What better than use a simple timer schedule and sample bit as I learn from fa far time ago than try understand a so cryptic code? I prefer mine not elegant as that but just  working out of finger on keyboard! No need to think about finger move themselves as they where on piano keyboard I was palying a song from what in memory.
 I am not able to play that song, it is too difficult to me and some advanced arpeggio are out of my actual standard ability too.

 Get back to our trouble... I see Sue word are concise and precise. I figure this example is confusing so I prefer her simple feel of thing on how to guide through all family member of TIVA. Just two or three line of clean and concise tuition than a long involute example!

Markel Robregado said:

Also, "Unlock from NMI default", has been documented at laboratory workshop pdf.

  Maybe Sue think this is better to point to, When I started lab workshop where not available. Now I go see what it is and if I can learn something.. This family, not TI limited, is too hard to learn and lack a lot of documentation.

me puede usted guiar para configurar los switch 1 y 2 como entrada, quiero es que al precionar cualquiera de los dos , me prenda un led