Android device uses USB serial port to transfer data

Source: Internet
Author: User

Start with two open source projects one is Google's Open source project:

The other is the open source project we introduced this time:


First step: Get all the plugged-in serial drivers

1 Usbmanager manager = (usbmanager) Getsystemservice (context.usb_service); 2 list<usbserialdriver> availabledrivers = usbserialprober.getdefaultprober (). FindAllDrivers ( Manager); 3 if (Availabledrivers.isempty ()) {4   return ; 5 }


We then select the first dirver to connect the device

1 usbserialdriver driver = availabledrivers.get (0); 2 usbdeviceconnection connection = Manager.opendevice (Driver.getdevice ()); 3 if NULL {4   //  probably need to call Usbmanager.requestpermission (Driver.getdevice (), ..) 5   return ; 6 }

Then we can read the data.

1 //Read some data! Most of the just one port (port 0).2Usbserialport port = driver.getports (). Get (0);3 Try {4 (connection);5 //set the baud rate, data bit, stop bit, check digit of serial port6Port.setparameters (115200, 8, Usbserialport.stopbits_1, usbserialport.parity_none);7 8   byteBuffer[] =New byte[16];9   intNumbytesread = (buffer, 1000);TenLOG.D (TAG, "Read" + Numbytesread + "bytes.")); One}Catch(IOException e) { A   //Deal with error. -}finally { - port.close (); the}

Of course, we can add a monitor to the serial port.

11Private FinalExecutorservice Mexecutor =executors.newsinglethreadexecutor ();22PrivateSerialinputoutputmanager Mserialiomanager;3344Private FinalSerialinputoutputmanager.listener Mlistener =55NewSerialinputoutputmanager.listener () {66@Override77 Public voidOnrunerror (Exception e) {88 Log.d (TAG, "Runner stopped.");99                 }Ten10 One11@Override A12 Public voidOnnewdata (Final byte[] data) { -13//TODO New Data -14                 } the15             }; -16 -Mserialiomanager =NewSerialinputoutputmanager (SPort, Mlistener);//Add Listener - //Monitor the data changes of the serial port in the new thread +Mexecutor.submit (Mserialiomanager);

If you need to accept large data, you may encounter a problem: the data cache and receive time is not enough, so that the data is overwritten or lost, we need to modify the serial port read cache

Change the Read_wait_millis and Bufsiz in Serialinputoutputmanager to the right size.

The operation of writing data is the method of calling port

Port.write (bytes, 1000);

In fact, this open source project has encapsulated a lot of drivers for us, all under the driver package, we can directly use it.

I have time for cp21xx-driven USB port to tell how to differentiate multiple USB serial ports


Android device uses USB serial port to transfer data

Related Article

Contact Us

The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion; products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the content of the page makes you feel confusing, please write us an email, we will handle the problem within 5 days after receiving your email.

If you find any instances of plagiarism from the community, please send an email to: and provide relevant evidence. A staff member will contact you within 5 working days.

A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

  • Sales Support

    1 on 1 presale consultation

  • After-Sales Support

    24/7 Technical Support 6 Free Tickets per Quarter Faster Response

  • Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.