libgpio example on Beaglebone

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Phishfry

Phishfry

Son of Beastie

Thanks: 932
Messages: 2,908

#26
I use the HDMI because this is a development environment for me. I like the option.
If I ever come up with a deployable option I would go BBB Green for lack of HDMI.
 

Snurg

Aspiring Daemon

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Messages: 794

#27
There are several companies selling touchscreens for BBB. Still not sure which is best. Preferring one that's best supported, and can be re-ordered later (often bad with chinese suppliers).

And then there is the question of WiFi support. Still looking around and trying to find out whether it is possible to combine such cape with touchscreen cape. Are they stacked like with Arduinos' shields?

Have to leave soon for some hours, appointment at dentist. Feeling like a board going to the soldering oven *shudder*.
 

aragats

Aspiring Daemon

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#28
There are several companies selling touchscreens for BBB. Still not sure which is best.
So, we have 2 types: resistive and capacitive and 3 possible interfaces: AIN, I2C and USB.
If it's a resistive touchscreen, it's most likely AIN (using 4 analog inputs), may be also USB. Capacitive touch panel operates with absolute coordinates, thus does not require calibration, most likely have I2C interface. I wouldn't use one with USB interface since it will occupy the single USB connector.
there is the question of WiFi support
First of all it has to be supported by FreeBSD. WiFi adapters may have 3 different interfaces: USB, SDIO and Ethernet. The latter is rare, but is very convenient since doesn't require any driver at all, I know one good and tested example, which also supports AP mode. I guess, USB adapters are the easiest, for SDIO ones you'll have to load an overlay to configure the corresponding pins. Also, if you you want to use the existing micro-SD slot for other purposes, you'll have to use MMC2 for such WiFi module. I believe you can find all the signals on P8 and P9 connectors, but will have to attach a passive adapter.
 

Snurg

Aspiring Daemon

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Messages: 794

#29
Great tips, aragats!
You definitely have done much research for what is actually good.

Yes, the touchscreen must be capacitive.
Calibration sucks.
And even worse, I experienced a bad drift with resistive touchscreen. Had an Arduino with resistive TS lying for a few years in a drawer, and it was heavily drifted (buttons' sensitive areas had moved a lot) when I turned it on again. I2C is definitely the way to go, the USB must remain free.

And the example Wifi module you linked at, this looks great!
Aside of the good documentation, it seems to be a manufacturer one can expect the stuff will be available next year, too. So no need for a blue beagle!

I'll order the BBB when I come back from the toothdriller.
The TS and WiFi aren't necessary anyway before I learnt to set up the OS etc on the BBB, so I have time for selecting the best.

This info was extremely helpful :)
Thank you very much again :)
 

aragats

Aspiring Daemon

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#30
Maybe I was wrong about recommending Newhaven displays, I cannot find any evidence of its touch panel support by FreeBSD.
They use FT5xx6 from FocalTech (FT5x06.pdf and/or FT5x46.pdf). Of course, the protocol is described, and one can write a driver based on another i2c one, or maybe it just works.
By the way, this question about them has never been answered.
I'll try to test the one I have, will have to install Xorg etc., maybe later this week. In Linux Xorg works with it using the regular evdev input driver "on top of" edt-ft5x06 kernel module.
 

aragats

Aspiring Daemon

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Messages: 921

#32
Yeah, but it's only 480x272 and the touchpanel is resistive...
I guess, that means any resistive touchpanel is supported: they all use AIN0...AIN3.
The datasheet is here. Its' good that only 16 LCD lines are used, saves more GPIOs for other purposes.
 

Nicola Mingotti

Well-Known Member

Thanks: 121
Messages: 308

#33
Oh guys, i red the thread yesterday night, i envy you so much that you are woking on the BeagleBone, that is pure joy! I had all the stuff working in Liunx: PWM, ADC, PRUS. I hope soon i can try all those features with FreeBSD.

For Phishfry, I agree with aragats about connecting to the BBB, the serial cable is the first choice for first connections. After that I reccoment you set up an IP and connect via ssh, then you can sshfs or use Emacs in tramp-mode which is my preferred way for remote programming.
There was a nice thing in Linux that I had no time to test in BSD, you can connect via RNDIS-usb-gadgets (Ethernet via USB). This is the uber-solution because with 1 USB cable you can power the BBB and contol it via ssh.

About wifi, I tested the BBB running FreeBSD-11.1 as AP, with ALFA AWUS036NH, it works. Also device ALFA AWUUS036NEH works but I don't remember if i tested it in AP mode.

About microSD. My miroSSD of choice is SanDisk Ultra class 10, 16 GB; I have 4-5 of those and they worked well in the last 6 months. I prefer to put all in the eMMC when the device is ready for deployment, micoSSD is just another thing on board that can fail with non negligible probability;)


Bye
Nicola
 

Nicola Mingotti

Well-Known Member

Thanks: 121
Messages: 308

#36
This post has the details from both consoles.
This worked on FreeBSD -CURRENT but in 11 RELEASE it now shows up as an ue0 ethernet device not a storage device.
Maybe it is now similar to Linux and uses RNDIS.
Now I am deep into the development of a web application (which I hope will make me richer;P). As soon as it reaches a stable state (matter of weeks) I will plug in my BeagleBones and try it. The BeagleBone is the most interesting comptuer I ever bought. I think I learnt more things in 1 year fightinig with the BBB than in 20 years on desktop/laptop computers. It is also so cheap I don't fear much to experiment with electronics and eventually to burn one;)
 

Snurg

Aspiring Daemon

Thanks: 326
Messages: 794

#37
The parcel with the BBB just arrived!
It seems genuine Farnell original.
Had to search a while, before deciding to buy at a reputable distributor, as many shops here offer clones of doubtful origin.

Now I am digging deep in my electronics parts boxes.
1488+1489 (datestamped 8201 and 8207...), RS-232 nullmodem cable, switching power supply +- 5 and 12V, sized about 2 cigarette boxes, 2.54mm rastered PCBs already unearthed.
I am glad I left some basic stuff when I dumped the ancient electronics stuff many years ago :)

Now I am thinking about how best to protect the Beagle from my cats.
They are quite electric.
I guess a simple nose touch could easily shock that poor Beagle to death.
 
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