EXECCTRL_JMP_PIN referenced but not explained

[dghoti]

"EXECCTRL_JMP_PIN" is refernced 3 times in the SDK without an explanation of how/where to set it. [ https://datasheets.raspberrypi.org/pico/raspberry-pi-pico-c-sdk.pdf page 59 ]

I did eventually find: static void sm_config_set_jmp_pin (pio_sm_config *c, uint pin) but it is a different call and the two are not linked. [https://datasheets.raspberrypi.org/pico/raspberry-pi-pico-c-sdk.pdf page 148, 152 ]

maybe explain "EXECCTRL_JMP_PIN" better, or change the reference to "sm_config_set_jmp_pin"

[Edit: corrected the page numbers to the ones on the page, not the literal PDF page]

[lurch]

EXECCTRL_JMP_PIN is the JMP_PIN field of the SM0_EXECCTRL, SM1_EXECCTRL, SM2_EXECCTRL & SM3_EXECCTRL Registers described on page 395 of the RP2040 Datasheet . Unfortunately the fields / registers aren't always referenced in exactly the same manner throughout our documentation, but it sounds like in this particular case if you searched for "jmp_pin" you would have found what you were looking for?

[dghoti]

I did search for jmp_pin which is how I found the example I quoted above - as a complete beginner in programming and my first attempts at using the pico, I found the reference for this in the SDK very confusing, until I found (and guessed) that it could be set with the sm_config_set_jmp_pin() function. The description on page 395 of the RP2040 datasheet is even more confusing for me - I would have preferred if the mention of it in page 59 of the SDK had shown how to set or use it, or even referenced the function on 148/152. No need to go to the RP2040 datasheet, as it is already in the SDK (which is the document that referenced it)

[lurch]

As "a complete beginner in programming", PIO probably isn't your best starting point!! It's a fairly advanced topic. And if you don't reference the RP2040 datasheet at the same time as the SDK documentation, I suspect you may find the SDK documentation even harder to understand.

Complete beginners are much better served by MicroPython https://www.raspberrypi.org/documentation/rp2040/getting-started/#getting-started-with-micropython which also lets you use PIO if you want. (Although unfortunately the MicroPython documentation still has gaps https://github.com/micropython/micropython/issues/6855 )

[dghoti]

I was merely trying to provide some feedback. I have managed to figure it out (as stated above) but it too me a few hours as the SDK mention of it was rather obscure in my opinion. maybe "complete beginner" is the wrong phrase, I do know my way around C a bit, which is why I prefer to use C over Python - which while I know is a popular language, I tend to prefer to avoid where possible. I do realise I am taking the harder path here, but I do prefer to stick to languages with which I am more familiar - the PIO assembly is giving me a hard time, but at least I can follow it and (to a degree) bend it to my purposes, though some others might not be as tenacious as myself - My belief was that the SDK was there to provide a reference, but to only mention setting the jump pin once, and not tie it to the part of the SDK that shows how seems to be a limitation. I am only trying to provide some feedback that might help provide clarity for others - since I have (eventually) found my own solution - which I had mentioned in the very first post. I guess next time, Ill just keep my mouth shut - apologies if I have caused any offense by my suggestions - I was simply trying to help. Thank you for your comments lurch, but I dont feel they were helpful or particuarly relevant to the issue I thought I was highlighting,

[lurch]

Hello @dghoti

I'm sorry if my reply came across a bit blunt last night, perhaps I was too tired and being overly-defensive :slightly_frowning_face: I'm afraid your "complete beginner in programming" threw me a bit!

We do welcome feedback and suggestions, thank you for pointing out which parts of our documentation you found confusing / lacking :+1:

[dghoti]

Hi @lurch,

Its all good - maybe I understate my programming abilities as I still consider myself an amatuer (compared to a lot of what I see here). Mistakes were made on my side too - you're a good egg!