Great post Bob, thanks for sharing. It'd be nice to have DeviceWrite work fast enough for PWM straight out of the box though. I haven't been able to get it to work following using your github files on my pi yet, but will certainly keep persisting. Have you got yourself an RPi2 and tested it out on that yet?

Hans,

I have not done an exhaustive check, but it looks like my code runs out of the box on the v2 model of the RPi. There are, however, some typos in my instructions. Here's the process I followed, so please tell me where things go wrong.

clone the repository. I made a directory called ~/test/ and put it there.

git clone git://github.com/bobthechemist/wiringPiLink.git

Now, cd ~/test/wiringPiLink and make two directories

mkdir wiringPiLink/LibraryResources
mkdir wiringPiLink/LibraryResources/Linux-ARM

I am fairly new to software distribution, and this is clearly not the best implementation. Learning how to distribute my projects more effectively is on the list of things to do...

Compile the library and move it to the directory you just created

~/test/wiringPiLink/compile.sh
cp ~/test/wiringPiLink/libwiringpi.so.1.0.2 wiringPiLink/LibraryResources/Linux-ARM

Create a simple circuit with an LED and resistor. I have connected the circuit's ground to the RPi's ground and the circuit's positive to the RPi pin 16 (GPIO 23 or in the wiring pi definition, pin 4). Note that my software currently only recognizes the wiringPi definition. Load up wolfram (don't forget to sudo)

sudo wolfram

Now you should be able to load the library and use it

<<wiringPiLink`
wiringPiMode[4,1]
wiringPiWrite[4,1]
wiringPiWrite[4,0]
wiringPiBounce[4]

Please let me know where things go wrong so I can fix the bugs and send a new commit to github. Thanks for trying out the code

Hans,

Please try one more thing; make sure the the lib file is in ~/test/wiringPiLink/wiringPiLink/LinuxResources/Linux-ARM and that you are running sudo wolfram from ~/test/wiringPiLink (the directory tree structure is quirky, I know). I'm not convinced this is the actual problem, since I get a different error when I reproduce this. However, I want to rule out directory structure.

Hi BoB,

I have just the lib file in the Linux-ARM directory

~/test/wiringPiLink/wiringPiLink/LibraryResources/Linux-ARM $ ls
libwiringpi.so.1.0.2

Running sudo wolfram from ~/test/wiringPiLink

pi@raspberrypi ~/test/wiringPiLink $ sudo wolfram

still produces an SPI error

  In[1]:= <<wiringPiLink`                                                         
    Unable to open SPI device: No such file or directory

I then ran gpio load spi and got an error

pi@raspberrypi ~/test/wiringPiLink $ gpio load spi
ERROR: could not insert 'spi_bcm2708': No such device
gpio: Unable to load spi_bcm2708

pi@raspberrypi ~ $ gpio load spi
ERROR: could not insert 'spi_bcm2708': No such device
gpio: Unable to load spi_bcm2708

hmm

Thanks BoB! As soon as I enabled SPI it all worked a perfectly. Looking forward to using it. Cheers Hans

Thanks for the update, Hans. I'm glad you've been able to make something out of WiringPiLink. (And I'm particularly impressed that you got the remote kernel up and running; I have found it very buggy and temperamental, but as you've no doubt noticed, being able to run the interface on a normal computer makes the Wolfram/RPi experience much more enjoyable.)

For what it's worth, Raspbian Jessie appears to drop the need for GPIO users to be sudo'd. I am finishing up another project at the moment, but my intention is to revisit WiringPiLink to make sure it works with the current hardware/software. Stay tuned.