Hello all,
Was playing a bit with my raspberry pi 4 this week end and needed to program some gpio but encoutered strange issue with proview.

Indeed I'm using gpio20 et gpio26 and have previously added pwrp user to he dialout group in the pi.
When doing manually (without proview) an export of theses gpio in /sys/class/gpio and playing with the "value" file its working fine (so hardware is fine).

When trying to do the same in proview nothing is living but no error.
The Gpio object returns IO-SUCCESS and the only strange thing is the GPIOModule object whch reveals "NO NAME NO MSG" or something similar but I don't remember if this is blocking or not.

I have no other errors in the terminal and proview log looks OK.
Program starts without issue and is running fine but even using the TestOn attribute of the Signal Do corresponding to my gpio I can't change the value of it (voltage doesnt change at the pin at all)

I was wondering if there is a special representation for the gpio signal to be used ? I tried Int32 and Bit8 / 16 / 32 but no luck. What else could it be ?

I m running out of ideas.It Seems an easy move but I m stuck there at the moment

Thanks for your help
Snarf

Hi Snarf,

I also tried the GPIO some month ago and I had to do some modifications to make it work. To make it work att boot I added a retry in the opening of the file in case ProviewR was started before the GPIO files were created. There also was something with the loop over the channels that I had to adjust, but looking at the code now I can't figure out exactly what the problem was and if there is any work around. It's possible that if you also create channels for the GPIO numbers that you don't use, without connecting them, it might work.

/Claes

Thanks for reply Claes,
Actually I'm not trying to start it from boot at the moment, I'm launching proview manually through rt_ini -i command.
So issue related to timing between gpio files and proview start. I even checked that gpio files are not created before Proview is started so it appears the files creation (and I guess further access) is right ?

What do you mean by sometheing in the loop ? You mean related card_Io_read and write method ? Can I check somehting and provide log for you in order to understand the probleme root cause ?

At last concerning your channel cration for unused gpio, you mean to create new ChannelDo and affect the number attribute to an unused gpio pin and leaving the channelDo unconnected to any Do signal ? Is that what you proposed I try ?

Thanks for your help
Francois

Hi Snarf,

Yes, it was the loop over channels in the write method, but the problem is fixed in the next version. It's just that I can't figure out if there is any work around for you in the present version.

I mean that you can test to also create ChanDo with number 1-19 and 21-25 to fill out the channel list in the loop, but you don't need to connect them. It's just a wild guess and might not work at all...

/Claes

Hi Claes,
Unfortunately filling the missing gpio bank didn't make the trick and I can't succeed to make my gpio work.
You mentionned it is working in further version, which version are you refering so I can test it because I do really need my gpio for my home automation
Thanks for your time
Snarf

Hi Snarf,

I'm referring to V6.0.0 that hopefully will be released next week.

/Claes