RPi librogpio first test release

Edit:
First snapshot release of rogpio with source and a BSD license is up!

edit again:
I was hoping to hide my awful URL, but I just noticed the HTML in the pages with the alternate URL has been messed with badly.
Go to this first link. I’m not sure what the other one actually does. Looks like some sort of Google Analytics stuff but I don’t know.

http://members.dodo.com.au/~izabellion1/librogpio.html

If you are game, or can tell me what is going on with the source, use this link.
http://experimentech.tk/

/Edit
For a while now I’ve been trying to work out a way to write a library to control the GPIO pins on a Raspberry Pi by using the native gcc compiler. Today I finally had a build that built properly and passed a simple test program of the implemented functions.
If you are after a fully featured way of interacting with the GPIO from gcc this is the opposite! Currently it should be enough for flashing LEDs, reading the state of an input and that sort of thing.

I need feedback from people with gcc set up on whether the static library even links. I haven’t included source yet because it needs work and expansion before I’d feel comfortable with people seeing it. You’ll have to take my word for it that there’s no intentionally malicious code. It should be fine to use as long as care is taken to use the right #define for the pi model for initialisation.
I’ve included compiled versions of the test program for Pis with 512 and 1024MB RAM. Please, oh please run the right one. Detection of the host system is on the wish list depending on whether anyone besides myself actually wants to use it.
The only real outside world interaction the test program has is toggling GPIO 21 and reading inputs from GPIO 19 and testing the pullup and pulldown of pin 19.

Yes, the compiled executables are huge at a bit over 1MB. It’s compiled with gcc. What can I say.

Anyway here’s a link to it.
https://www.dropbox.com/s/1zy8oufsojyv4d2/rogpio.zip?dl=0
Hope this first release works for you.

Please provide feedback in this thread, but remember this is just the first version which actually functioned without smoke and mirrors. Look at the functions in the header to see what is supported.

I have had a quick look. (Dropbox and NetSurf are just so not together.) The test built OK on my RPi3.

FWIW elf2aif does give a smaller executable.

(Dropbox and NetSurf are just so not together.)

So true. The file had to go Pi Zero → Orange Pi PC → Pi 3 to get it to Dropbox. If you know a better alternative please tell me.
Thanks for the tip too. I’m sure there’s a lot that could be done to get that executable size down. I think my library was only about 5k.

Glad it didn’t break horribly. That gives me some confidence to continue.

If you know a better alternative please tell me.

why not create a samba share on what ever machine you have dropbox mounted on, sharing the dropbox folder, and then mount it using OmniClient / LanMan98?

Michael, theoretically I could do that with an NFS share too however it’s only half the issue. Dropbox is very NetSurf unfriendly, so it’s hard for someone to open the link and try it. What I need is a solution for uploading files somewhere which has a simple interface which can be accessed easily.

I haven’t had any time to work on any additions since I put the archive up. However I did fix some problems with my Orange Pi based NAS which should make things easier for me. Essentially managed to stop lightdm from starting (it’s stubborn!) and stick a big crude heatsink onto the chipset to stop it from overheating during intense activity.

I want to add some more GPIO chipset support and device autodetection to make the executables more useful, then maybe move on to i2c and UART. I think I saw that UART HAL support was added in for the Pi 3 recently?

So true. The file had to go Pi Zero → Orange Pi PC → Pi 3 to get it to Dropbox. If you know a better alternative please tell me.

A RISC OS FR subdomain? :)

Chris Gransden put this up https://www.riscosopen.org/forum/posts/search?page=3&q=dropbox&submit=Go halfway down the page with instuctions

It looks like I wrote but didn’t send. Typical.

David, I like the way you think. It would be an appropriate place.

Before I saw these messages today I remembered that I had an ancient and crusty website that apparently I hadn’t touched in nine years or so. It has very little space but it will do better than dropbox for the time being. I grabbed a free domain to slap over the awful ISP issued URL. It seems to work fine in NetSurf so it should be a bit more accessible to people.
Here’s the URL. Follow the “RISC OS” link in the list on the left. There’s a link on the page to the .zip
experimentech.tk

Rob, the files people put up using the direct links didn’t seem to have the right permissions on DropBox. Maybe they changed something. It seems to bring up the download page that breaks on NetSurf still. I’ll have to have a play for myself when I have some time.

I haven’t really had any time to actually do much, but I have been reading and planning the next addition.

The executable size issue was easily dealt with. Stripping it makes a massive difference.
Example: I changed test.c so it only had the couple of lines to enable PWM audio on the Pi Zero plus the printf(because I needed it). Adding -s to the gcc options bumped it down from over 1.1MB to 156k. Running it through elf2aif only netted a 1k saving. Odds are if I removed stdio and of course the printf it’d cut the size down more.

Sure, turning on the audio could be done with probably less than 20 lines of assembler, but that’s beside the point. Still, not too bad for something with a static library.

I am still working on this!

Time has been a little short recently but I’ve added a few functions. I’m also working on a very simple but hopefully effective means of the code choosing the correct GPIO base at runtime. This is sorely needed to make the library useful.
A 32 bit peek and poke has been added. There is also support for setting and checking for triggered events like rising edge, falling edge, high, low etc. I haven’t added any interrupt support though so the code still needs to poll.

A bit more work and testing is needed before the next release. Serial, IIC and SPI will be in a later release. I just want to get something out with a little more functionality.

Does anybody know what license the source could be released under? I don’t really care what people do with the code. In fact My intent is for people to use the library code itself or look at it and say “I get it! I bet I can make it better”.
Pretty much the only thing I want is to be acknowledged as the original creator.

I’m working on chasing bugs right now after a break for sickness. I just want to get the source out there now, because too much has gotten in the way and it’s taken me far too long to get this far.

BSD or MIT like licence?

In fact My intent is for people to use the library code itself or look at it and say “I get it! I bet I can make it better”.
Pretty much the only thing I want is to be acknowledged as the original creator.

Yay! Nice to see more and more people who actually understand what open source means.

BSD seems to be clearly understood by the GPL brigade.

I finally added a BSD license and uploaded the source.
I added to the first post to reflect this.

Please go to my site and click on the RISC OS link on the left to find it.
http://experimentech.tk/

I’m calling it a snapshot release because I honestly haven’t had time to tidy up the loose ends / squash bugs but wanted to get it out there finally.