I want my android tablet to have multiple displays, specifically with a wireless projector. I have a Diamond Video Stream adapter that runs perfectly when i run multiple displays on my laptop with the LCD projector wirelessly. I just installed the DisplayLink USB Graphics driver then it works.
Now, what i want is to do the same thing with my android tablet; To just connect the Diamond Video Stream's USB device to the android tablet (via mini usb to usb cable) and display what ever is happening on the android tablet to the LCD projector wirelessly.
Can anyone lend me a hand on this one?
Thanks.
Quite probably your tablet's USB just support USB OTG, meaning you can connect usb drives or input devices to it, but I doubt you can hook an USB display adapter.
Depending on your intended use, you can attach your projector to a DLNA media renderer and send video or audio streams via a DLNA media streamer app like twonky:
Twonky Beam
Should your phone support USB OTG, then DisplayLink technology will work.
In the product you mentioned though, you also have a wireless part.
The Samsung wireless USB chip driver is unlikely to be in the phone and, because it's not DisplayLink technology, it is not included in DisplayLink application in the store.
Related
I’m trying to set up an Android Open Accessory environment with no success. I’m using the PIC32MX250F128D controller on my board, I’ve implemented a Firmware that works in USB Host mode and handles all the Android Open Accessory Protocol. I have also an Android App to detect any external hardware plugged in the USB conector. The problem is that I’m not getting any USB “physical answer” from the tablet. From the USB 2.0 Standard (and from this document as well https://source.android.com/accessories/aoa.html ) The Accessory (the external hardware), acting as a USB Host, should wait for a 100miliseconds signal from the USB Device (Android Device, tablet, smartphones, etc..). That’s the very first step on the USB Phy Standard. What might be happening is that the USB on the Tablet side is acting as a Host and also waiting for this signal from an external Hardware. Is there any android configuration that enables USB open accessory, or something like that? Also, How can I know in which mode the USB in android is operating, or what is the "normal" mode USBHost or USBDevice?
Finally I've got it solved :). I wasn't able to detect any hardware signal, the hardware signal is either D+ or D- pin set to high and the other to low. If D+ is set to high the USB Device operates in full-speed mode, otherwise in low speed mode. I've found out that Android works in host or device mode looking at the cable plugged in. My cable was telling android to operate as host, so I didn't receive any Device Attach signal from Android.
is it possible to screencast from an android phone with either slimport or mhl support to a laptop with the usual usb charging cable of the phone?
No.
First, "the usual usb charging cable" does not have the extra pins used by MHL or SlimPort.
Second, only a laptop with MHL, SlimPort, or HDMI input could receive a signal, even if you had the right cable. You can get some HDMI input devices that work with a laptop for recording purposes (BlackMagic has one IIRC). I am not aware of any similar hardware for native MHL or SlimPort, though stuff could exist.
In the various tutorials for building an Android accessory that uses a USB connection, the first step is to "Select a hardware platform that can support USB host mode." Most of these tutorials claim that that means obtaining a device that is running > Android 3.1 (or one that is rooted, or a tablet, etc.).
In my testing, it seems that, for a phone to support USB host mode, it not only has to be running > Android 3.1, but must also supply power over the USB cable. Can anyone confirm or deny this?
Most tablets seem to supply power over USB, but many phones do NOT. I can't find any place that will directly state that the phone must supply power over USB in order to be able to run an accessory as they all seem to loosely state that anything running >3.1 will work (as long as, at least, the device you're connecting to the phone supplies power). However, in all USB libraries that I've tested, I can make a connection to my USB device just fine from my tablet (which DOES supply power over USB), but I can't get any of them to work with my phone (which does NOT supply power over USB). Both are running > Android 3.1.
Note that I'm not trying to power my accessory over USB. My accessory has its own 5v power source and can even supply power over USB. I just want to build an app that will allow my phone to be able to connect to it, change it's settings, receive data, etc., but I can't get my phone to recognize if/when the device is connected. I don't know if that's because of my phone's unpowered USB, or if it's because of another problem with my phone and/or software. Unfortunately, I don't have another >3.1 phone to test with.
As a side note, the device I'm connecting to is an FTDI/Arduino board that I'm working on which, again, connects to the (powered) tablet just fine, but the (unpowered) phone claims that no USB devices are connected (even though the FTDI board supplies its own power).
Your Android Device needs to have OTG Hardware built in, you can not add it to your phone, most high end smartphones have OTG built in, Samsung Galaxy series does, this allows connection with external USB slave devices, you do need a USB Cable that is OTG which connects pin 5 to GND, this enables the OTG and then supplies power to the device, Like USB Flash memory, if you want to connect an Arduino, you will need an external power source.
As a side note, the device I'm connecting to is an FTDI/Arduino board that I'm working on >which, again, connects to the (powered) tablet just fine, but the (unpowered) phone claims >that no USB devices are connected (even though the FTDI board supplies its own power).
This leads me to believe that your tablet is OTG, and you phone is not.
Well, considering your target area, you might not want risk frying your device before starting to understand the internal pin structure of USB connectors.
I suggest that you use a low-cost non-brand unit. I just discovered this while researching how to direct-solder a +5V DC power source on my broken tablet's PCB, so old that its damaged micro USB port can't be replaced. Normally, an in-market, low-cost, phone-sized Android device (various non-brand products, most of China manufacture) has a very low-power battery attached; no OTG option to play with. It's just getting connected with a PC/USB host to get power for charge and communication over USB/ADB. Almost all of the units I've bought above 7" display size, support even USB 2.x drive as external storage, meaning that OTG is enabled by default.
Try with some other devices from your friends/family/collegues -- just to connect an OTG cable and maybe an USB drive with a built-in LED for easier identification without the PC/Controller device -- if you have enough "test subjects) and they trust you to connect a storage device.
I want to build a device with sensors (either with an Arduino or a homemade circuit with a microcontroller) and I want to send data from it to an Android device via an USB cable. What is the library required to connect devices via USB? Is there any documentation I could read for it? The problem is that whenever I search for this I only get results about the ADK and their board, not for other devices.
Are there things I should know beforehand? I'm not new to either field, but it's my first project with the two connected.
Thank you.
The first thing to check is if your Android device is equipped with USB host interface. In such case you can connect a regular USB device to your Android and use this API to communicate with the device.
However, typical Android device (virtually every mobile phone) is only equipped with USB device interface, for connecting to PC or another USB host. In such case you have to use the Android's USB Accessory support. The most important idea behind Android Open Accessory protocol is that it swaps (logically) USB device and USB host roles. It's the USB host that looks for the device with particular vendor/product ID, selects particular USB protocol interface, and then simply uses the in/out bulk endpoints found to communicate - pretty smart, isn't it?
To build Android Open Accessory compatible device you then need a CPU with USB host interface. If you want to use Arduino, this shield is probably a good starting point, given its firmware implements Android Open Accessory Protocol already. There are some example applications as well.
This works great on my Nexus7 which is connected over the OTG to Arduino Mega.
Android USB host serial driver library for CDC, FTDI, Arduino and other devices.
Hope it helps!
You have two solution
1: Your Arduino board act as a USB host and power the Android device.
With this solution you have to implement and USB Host stack on your Arduino board and must implement Android Open Accessory Protocol. Your Arduino board must power the Android device. Then you app must use the USB Accessory API to communicate with your board.
Avantage:
work with almost all Android Devices (no need for an USB Host port on Android device)
Disavantage:
The device board is more complicated (must provide power for both devices)
Firmware is more complicated (must implement USB Accessory mode)
2. your Arduino board act as a USB device and the Android device powers
you board.
With this solution your do not have to implement a specific USB protocol. Your board will act as a standard USB device. Since you act as a device you can power your board directly from the USB cable (the Android device will power itself and your baord). To communicate with your board you will use the USB host API of Android.
Avantage:
the device board is very simple
the firmware is simple and easier to debug (you can even test it with you PC)
Disavantage:
Works only with Android devices that have an USB Host port
On most device you will need a specific cable or adapter (ex :otg usb host cable)
I have experience with solution 2, and it works pretty well. All source code for the Android source is available from the link below. I have verified that it works with sensor devices from the company where I work on the following Android devices:
Samsung Galaxy S3
Acer Iconia tab a200
Asus Tranformer Pad TF300T
But it should work on most tablets and recent phones you can see this post if you want look at our experience.
I am looking for a way to communicate with a control-board (u can consider it a sensor device) using USB cable. My sensor device supports usb but I think android does not have a way for that.
Can that be possible through Bluetooth dongle?
Is there any Android device available which supports USB host.
USB host has been "hacked" into a lot of android phones, but it's not very user friendly and weird cabling is needed along with a power supply as the phone won't power a usb device.
Some of the "first generation" android tables apparently had USB host on some models.
I've seen pictures of a Xoom connected directly (via a short OTG cable) to a thumb drive that it appears to be powering and reading from, apparently it was unofficial software.
As for your other questions, yes, you can use bluetooth if you get a bluetooth modem for your embedded device. Or you can use wifi. Some of the phones have low voltage debug serial ports. Or you can build a modem / DTMF control interface to connect to the headphone jack...