I physically moved my android things project to a new physical environment. When plugged in to that environment, it now constantly reboots and power cycles. In my development environment the power remains stable and Android Things actual launches.
In the new environment, occasionally it may launch and actually display, but for the most part in that environment, it just restarts and reboots repeatedly.
I've tried 2 different usb cables, standard ones that charge various android phones.
What is the best practice for keeping Android Things power stable in any physical environment?
When plugged in to a new environment, it now constantly reboots and power cycles.
Most likely the problem is the power supply which isn't powerful enough for Pi 3.
It is officially recommended to use a power supply of 2.1 - 2.5A
I've tried 2 different usb cables, standard ones that charge various android phones.
In most cases USB cables used for regular Android phones aren't enough for Pi 3.
Related
I need to run tests against physical mobile devices, and need to deploy unit tests to many concurrent devices at the same time.
Conceptually, this is similar to the Xamarin Mobile Test Cloud, or Microsoft Mobile cloud... but I need an on-premise equivalent so that I can test Bluetooth and GPS features
I'm looking to test 7 to 14 physical devices all connected to the same USB hub.
Question
How many devices can a single Mac / Windows machine talk to over a single USB port?
What are the power considerations I need to keep in mind while selecting hardware?
Here is a visual example of what I imagine, however this device is focused on charging, not connecting a USB backplane to a computer.
Per USB controller you can have a 127 devices (128 minus the controller), bu I am not saying you can simultaneously have 127 devices communicating to the host and maintain any type of data throughput, that is a different story....
The core USB issue with a lot of devices is the power draw. We use special Y cables that have a data only side and a power only side even when using the so-called "powered" USB hubs.
The really good cables that do this are typically found via companies that cater to audiophiles and as such are typically very expensive and work great but are overkill for this usage. But also avoid the cheap Y-cables where the data-only side is "ungrounded" as you will have data transfer failures. Low quality cables will kill data through-put and have you running in circles chasing test failures.
Consumer external USB hubs are not created equal and wildly vary in their power output and simultaneous throughput across each port. While most will do well with one/two devices talking simultaneously, many start failing when 4-8 devices are all talking. Also trying to cascade them for increasing the number of ports can cause failures across the entire chain. Make sure you have a good return policy where ever you can buying it from.
You did not stated the testing framework, but some Appium info:
For Appium-based Android testing I have use a combination of:
Android<-USB->Host(adb)
8 devices is about the threshold for reliable simultaneously (bi-directional) testing
Android<-Wifi->AP<-Host(adb)
A DHCP server handles assigning an IP to the Android device via MAC address so we can create a static mapping of ports to IPs for remapping via adb
8 simultaneous Appium servers (thus devices) running per Window server/host is about what to expect
This works for about 32/64 devices per dedicated AP.
Remember the AP has to be ~4/5 feet away from the devices for proper signal attenuation
Mobile cloud datacenters use EMI / faraday cages to isolate each mobile device rack where multiple servers, an AP and the devices are installed within each rack
Android<-USB2Ethernet<-Host(adb)
Not all devices support OTG, so this is not always an option, but works great.
A DHCP server is required just like the Android<-Wifi->AP setup
iOS is a totally different can of worms:
4 iOS devices connected to a Mac is about all you can achieve with reliable results.
Remember a separate Xcode Instruments is spun up per Appium server on the host.
Mac Minis work great for dedicated Appium test servers.
In terms of GPS testing, mocking is the easiest way to go. There are hardware devices designed for GPS testing that are use by the top tier app developers (mapping, traffic, avionics, etc..) but for an ad-hoc in-house device lab these are usually way to expensive to purchase and setup (EMI / faraday cages are needed enclosing the device and the GPS injector antenna).
Bluetooth can be a big problem in a device lab due to interference, pairing issues, etc..., having a number of devices in close proximity competing for a single (or more) bluetooth accessory can make the accessories fail to pair with any device. Basically bluetooth testing simultaneously does not work well, but you can use Appium to automate the turning the wifi/bluetooth/airplane mode on/off, but for Android devices this requires that they are all USB connected and not using adb to remap host ports to IP addresses over wifi...
We are currently working on a project with a Raspberry Pi 3 B that will run Android Things NIH40K, 0.4.1-devpreview, Jun 15, 2017. As it runs A.T. I would like to connect two separate displays, one touch screen-module (Link) so user can interact via calculator app (making calculations) and one display-module (Link) that shows the outcome of the calculation.
We would like to know what technical (hardware and/or software) requirements we need to keep in mind and if it is possible (and how we can) to support the hardware within this setup?
In Windows XP SP3 is there a registry key or some setting, maybe even at the device level in the registry, that an EHCI USB 2.0 High Speed hub can be enumerated as a UHCI or OHCI full speed device at the host level?
I am seeing an issue where a USB 1.1 full speed device is deadlocked due to infinitely NAKd split transactions with the transaction translator buffer on a high speed hub. This only happens under certain circumstances the full speed device is connected behind a 2.0 high speed hub only in XP SP3. I have opened an issue with Microsoft and they have confirmed this is a known issue and there is no Hotfix for the issue (nor will one be developed). It has been corrected in Vista+.
If the device is connected directly to the host controller, or has a full speed hub upstream of the high speed hub the problem goes away (because there are no split transactions). So, if there is a way to force the high speed hub to enumerate as a full speed device then it may help us out.
Furthermore, the hardware design is set in stone. Systems have been developed and there is no way to insert a full speed hub chip anywhere in the design, or hook up the devices directly to the root hub. And finally, it is not an option to upgrade the OS on the systems.
After some work and research with help of Microsoft the current conclusion is that there is not a way to do this.
The workaround that we will be using is to perform a PnP reset on the bus to stop the infinite NAKs, then reopen the port to begin communication again. This is not very clean, but it will solve the problem.
I have been long interested to develop on the platform. I even got the tools installed already on my desktop but I can't upgrade my WDDM from 1.0 to 1.1. To make things simple: my graphics chips are not up to the task of running the emulator.
If I still buy a Windows Phone (e.g. a Nokia Lumia) for development purposes, can I sideload and test my apps there efficiently instead of going against the emulator?
If I still buy a Windows Phone (e.g. a Nokia Lumia) for development purposes, can I sideload and test my apps there efficiently instead of going against the emulator
Yes, of course. It's very easy and convenient. You have debugger and all the goodies. Advantage of the emulator is the test option for 256MB devices.
That's exactly what I used to do prior to upgrading my devstation. The nominal min spec says 3G but with a real phone it worked fine in 2G and as you say this also sorts out graphics limitations.
Note that the setting for whether the emulator or physical device is used is stored in the project, so if you accept a project from someone else you will have to set it once prior to debugging.
Well there are 2 sides of the coin. With the physical device you can test most of the things, but with a few limitations
You will not be able to test internet related test cases - For example, if you have an app which uses internet connectivity then you will not be able to test it on the device easily because
The device does not use the machine internet connectivity
When connected to the PC the device's internet connectivity(Data connection 3G/ wifi/GPRS) is broken.
You will have to purchase an account right from the first day you want to test your app. If you have the emulator working then you could postpone this for atleast few days.
Pretty much as the title says, using bootcamp.
WDDM1.1 compliance and GPU recognition confirmed by the WP7 emulator running with EnableFrameRateCounters showing.
I'm considering a Macbook air as a compromise to resolve a need to access iphone dev tools and upgrade my Win7 mobile capability to something reasonably performant with one device.
My current laptop barely runs Win7 and borders on unusable for WP7 tooling hence the interest to try and solve two problems with one device - if realistic.
I assume if the device can run WP7 tools satisfactorily, it would be capable of anything else I might want to do when booted under Win7.
The new MacBook Airs do not have very powerful processors. The 11" maxes at 1.66 Ghz, while the 13" maxes at 2.13 Ghz. However, they do have the same GPU as the current 13" MacBook Pro. Also, since they use solid state drives, data access is significantly faster. Overall, it will not be the fastest computer you've used, but it should be enough to work.
I've bought one, but since it's going to the wife, I won't be able to test it in depth.
Instead, the MacbookPro 13" from '09 works fine (monoTouch+iOS dev and bootcamp to vstudio+wp7 dev). I upgraded to 4 gigs memory and that helped, also the disk is slower than I'd like. It responds like a mid-grade desktop, imo.
The problem I see is that the processor on the air's is ULV with a really slow clock, also the sdd in the base version is only 64g which is going to be cramped, I think.
Consider this: many Mac gamers install Windows with bootcamp just to have better gameplay experience.
That's because Windows have native access to the GPU through bootcamp.
http://www.mth.kcl.ac.uk/~shaww/web_page/grid/macgpu.htm (2009 article)
http://www.gpgpu.org/forums/viewtopic.php?t=3766&highlight=bootcamp (2007 article)
So the answer is yes.