The code came from Derek Molloy’s Exploring Beaglebone -Tools and Techniques Chapter 9 page 362 Listing 9-10. Regarding a decent book on how to spidev have you any recommendations? I am the first to admit I am a novice and it goes without saying that we all started somewhere as frustrating as that is. So to recap add code to trace code? That sounds like a plan. All aside the real question on my mind is that I would like to rule out that there is not something else going on here with the device tree overlays that I would not be aware of? It would be helpful at this end if a guy knew where to look for updates (i.e. the source) and had a listing of what they were or how they might affect things downstream. I know how ridiculous that must sound in that Linux is an open source community backed by volunteers nonetheless I am not clear on the structure on how things come together and as such I find it utterly amazing that things work. I understand that Robert has had a big hand in it and there are many others, but I am not sure on how it all comes together. Thanks for the input no offense taken.
Thanks Robert. I will give it another whirl.
The code came from Derek Molloy’s Exploring Beaglebone -Tools and Techniques Chapter 9 page 362 Listing 9-10.
Yeah, I own the book too, but to be honest, I’ve only read a couple pages. Mostly because most of the material is remedial for me. I’ve been programming since the early 90’s, and that is not to say that I know everything. Because I don’t. But I have enough development experience that it usually does not take me much to wrap my head around many concepts. A couple days toying around with the code usually.
Regarding a decent book on how to spidev have you any recommendations?
No but I can tell you what I’d do in your shoes. I’d google, and experiment with what I find. Then continue toying with my own code until I found something that works for me. This process for me usually takes between 2 days, and a week for most things.
I am the first to admit I am a novice and it goes without saying that we all started somewhere as frustrating as that is. So to recap add code to trace code? That sounds like a plan. All aside the real question on my mind is that I would like to rule out that there is not something else going on here with the device tree overlays that I would not be aware of? It would be helpful at this end if a guy knew where to look for updates (i.e. the source) and had a listing of what they were or how they might affect things downstream. I know how ridiculous that must sound in that Linux is an open source community backed by volunteers nonetheless I am not clear on the structure on how things come together and as such I find it utterly amazing that things work. I understand that Robert has had a big hand in it and there are many others, but I am not sure on how it all comes together. Thanks for the input no offense taken.
Here is what I think, and pretty much I’ve stated it already. I think you’re inexperienced, and you need some time working with something that works. So here is what I’d suggest. Forget about Ubuntu for now, and use exactly what DR Molloy used in his book, which if I recall correctly was Debian wheezy. Exactly the same kernel however probably will not be necessary.
The point of using Debian and not Ubuntu is not what is about whats best, or better, or all that OS / distro zealotry. Instead, it’s about what’s best to set you up into a productive learning pattern. After which, when you’ve learned enough about Linux, and the Linux programming API - Perhaps you’ll be able to switch to another distro. Or perhaps you’ll come to find that Debian is really where you want to be.
As for this specific community. I do not think anyone here who posts at least semi regularly is above trying to help another person having issues. However there is a point where “we” start feeling like we’re doing too much work for someone else, who really needs to learn these learning points on their own. Mostly because they’re basic learning points everyone has to learn on their own to fully understand what’s going on.
One key point: If you understood the Linux operating system better, you’d realize that /dev/spidev* is a file that when having issues you just ls /dev/ and see what shows up . . . which is very basic troubleshooting 101.
So it’s not that I think you’re stupid. It’s that I think you’re at where I was 3 or so years ago when I first started with the BBB. Which was my personal first experience with embedded Linux. But, I’ve also had Debian experience going back since the early to mid 90’s . . .
Dean,
By the way, I think it’s great that you seem to be using a virtual machine for test development. This is something I do myself too.
In fact I wrote a smallish web server like app in C to display CANBUS data out over a websocket. Initially this code was developed on an i386 virtual machine, until I was happy with the results. Then porting the code to a beaglebone was as simple as copying the code over, and compiling native. . . . Anyway, I wish this was a point more people understood.
Interesting. Just reloaded with an updated kernel and this time it did not crash. All the same similar problems remain. William all things equal if you found the book remedial I would like to challenge you on that. Buy yourself an LCD and see if you can replicate what Derek Molloy did there in Chapter 9 page 362 Listing 9-10 - we both know talking and doing are not the same thing. For now I must dig deeper. Some of his examples were not nearly as frustrating. It’s a great book by the way. I could of started with arduino, but noooo I started with BBB.
I’m a programmer, and not an electronics engineer. However, I’ve already done bare metal LCD with an MSP430, so I doubt the BBB would present much of a challenge . . .
For the sake of us who don't have the book..
Which LCD? Controller? Model etc?
a lot has changed since 3.8.x, you never know as there maybe a driver for it..
Regards,
Newhaven Model: NHD-0216K1Z-NSB-FBW-L.
He is also using an accompanying 74HC595 8 bit serial shift register in a 4 bit (interface DB4-DB7 configuration).
4.1.12-ti-r29 UTC 2015 armv7l GNU/Linux Debian Image 2015-11-12
Dean,
By the way, I think it’s great that you seem to be using a virtual machine for test development. This is something I do myself too.
In fact I wrote a smallish web server like app in C to display CANBUS data out over a websocket. Initially this code was developed on an i386 virtual machine, until I was happy with the results. Then porting the code to a beaglebone was as simple as copying the code over, and compiling native. . . . Anyway, I wish this was a point more people understood.
That sounds like some very handy code. Is it in open source space anywhere?
That sounds like some very handy code. Is it in open source space anywhere?
No.