# Usb-serial not connection on android **URL:** \ **Category:** Bugs and troubleshooting\ **Created:** [October 2, 2019, 2:53pm UTC](https://forum.realdash.net/t/usb-serial-not-connection-on-android/159 "2019-10-02T14:53:20Z")\ **Posts on this page:** 16\ **Page:** 1
**Author:** ![CoTECH](https://forum.realdash.net/user_avatar/forum.realdash.net/cotech/32/8_2.png) [@CoTECH](https://forum.realdash.net/u/CoTECH)\ **Post date:** [October 2, 2019, 2:53pm UTC](https://forum.realdash.net/t/usb-serial-not-connection-on-android/159/1 "2019-10-02T14:53:20Z")
The essence of the problem is that every time I use the RDCan protocol and the serial port, my arduino nano device does not connect to RealDash, or rather, with luck, it can connect, but after changing the device I can’t connect again. At what on Win10 this device works without problems. I am using Android 7 (N) ---
**Author:** ![realdashdev](https://forum.realdash.net/user_avatar/forum.realdash.net/realdashdev/32/6_2.png) [@realdashdev](https://forum.realdash.net/u/realdashdev)\ **Post date:** [October 3, 2019, 7:08am UTC](https://forum.realdash.net/t/usb-serial-not-connection-on-android/159/2 "2019-10-03T07:08:50Z")
What Android device is this? Please note that USB-Serial communications rarely work on Windows based Android simulators. ---
**Author:** ![CoTECH](https://forum.realdash.net/user_avatar/forum.realdash.net/cotech/32/8_2.png) [@CoTECH](https://forum.realdash.net/u/CoTECH)\ **Post date:** [October 4, 2019, 10:29am UTC](https://forum.realdash.net/t/usb-serial-not-connection-on-android/159/3 "2019-10-04T10:29:29Z")
I figured it was a bad HUB Close this topic ---
**Author:** ![CoTECH](https://forum.realdash.net/user_avatar/forum.realdash.net/cotech/32/8_2.png) [@CoTECH](https://forum.realdash.net/u/CoTECH)\ **Post date:** [October 4, 2019, 7:02pm UTC](https://forum.realdash.net/t/usb-serial-not-connection-on-android/159/4 "2019-10-04T19:02:14Z")
Although not. The problem is repeated. Again and again. The point is that if I use a new example for the Arduino RealDashCan 2, then it does not work on Android, but it works on Win 10. But if I download an old example for Arduino, this is where there is no “memcpy”, then this example starts working on android and Win 10 … Can you take a look? ---
**Author:** ![CoTECH](https://forum.realdash.net/user_avatar/forum.realdash.net/cotech/32/8_2.png) [@CoTECH](https://forum.realdash.net/u/CoTECH)\ **Post date:** [October 4, 2019, 7:03pm UTC](https://forum.realdash.net/t/usb-serial-not-connection-on-android/159/5 "2019-10-04T19:03:45Z")
I do not use emulators. Standalone device -android standalone -win 10 ---
**Author:** ![realdashdev](https://forum.realdash.net/user_avatar/forum.realdash.net/realdashdev/32/6_2.png) [@realdashdev](https://forum.realdash.net/u/realdashdev)\ **Post date:** [October 5, 2019, 10:03am UTC](https://forum.realdash.net/t/usb-serial-not-connection-on-android/159/6 "2019-10-05T10:03:10Z")
Could you be using non-arduino device that has big endian processor? ---
**Author:** ![CoTECH](https://forum.realdash.net/user_avatar/forum.realdash.net/cotech/32/8_2.png) [@CoTECH](https://forum.realdash.net/u/CoTECH)\ **Post date:** [October 5, 2019, 1:28pm UTC](https://forum.realdash.net/t/usb-serial-not-connection-on-android/159/7 "2019-10-05T13:28:54Z")
For example? ---
**Author:** ![CoTECH](https://forum.realdash.net/user_avatar/forum.realdash.net/cotech/32/8_2.png) [@CoTECH](https://forum.realdash.net/u/CoTECH)\ **Post date:** [October 6, 2019, 11:57am UTC](https://forum.realdash.net/t/usb-serial-not-connection-on-android/159/8 "2019-10-06T11:57:59Z")
Stm? Esp 32? ---
**Author:** ![CoTECH](https://forum.realdash.net/user_avatar/forum.realdash.net/cotech/32/8_2.png) [@CoTECH](https://forum.realdash.net/u/CoTECH)\ **Post date:** [October 6, 2019, 12:39pm UTC](https://forum.realdash.net/t/usb-serial-not-connection-on-android/159/9 "2019-10-06T12:39:28Z")
> [@](#): > > Could you be using non-arduino device that has big endian processor? … I quote one article about a sequence of bytes… > Conclusion > It is unfortunate that a universal byte ordering system was not created at the beginning of the digital age. I don’t even want to know how many collective hours of human life were devoted to solving problems caused by not matching byte order. > > In any case, we cannot change the past, and we are also unlikely to be able to convince every company that manufactures semiconductor technology and software to revise its production lines to achieve a single universal byte order. What we can do is to achieve consistency in our own projects and provide clear documentation if there is a possibility of a conflict between the two components of the system. ---
**Author:** ![CoTECH](https://forum.realdash.net/user_avatar/forum.realdash.net/cotech/32/8_2.png) [@CoTECH](https://forum.realdash.net/u/CoTECH)\ **Post date:** [October 6, 2019, 12:48pm UTC](https://forum.realdash.net/t/usb-serial-not-connection-on-android/159/10 "2019-10-06T12:48:09Z")
So! Now we clearly know that RealDash uses direct byte transfer, or as it is also called - the network data transfer order … And using arduino, which uses a non-direct (reverse) byte order, is not quite the right approach. And we learn about this only now)))) after so many years of crutches and correspondence)))) Well … For me this is a very good lesson in terms of self-development! Then I will take all my projects to a new level. Apparently the time has come))) But still? Which controller do you recommend as more suitable for communicating with RealDash? ---
**Author:** ![CoTECH](https://forum.realdash.net/user_avatar/forum.realdash.net/cotech/32/8_2.png) [@CoTECH](https://forum.realdash.net/u/CoTECH)\ **Post date:** [October 6, 2019, 1:23pm UTC](https://forum.realdash.net/t/usb-serial-not-connection-on-android/159/11 "2019-10-06T13:23:37Z")
But I can still try my luck, and use the Internet shield for nano, thereby I can transfer data over a network protocol without violating the order of Big-endianess? Right? Or change the controller? Which compound is better? More stable? Faster? Network or USB? ---
**Author:** ![CoTECH](https://forum.realdash.net/user_avatar/forum.realdash.net/cotech/32/8_2.png) [@CoTECH](https://forum.realdash.net/u/CoTECH)\ **Post date:** [October 6, 2019, 7:11pm UTC](https://forum.realdash.net/t/usb-serial-not-connection-on-android/159/12 "2019-10-06T19:11:43Z")
Give an example of a big - endianess controller? ---
**Author:** ![CoTECH](https://forum.realdash.net/user_avatar/forum.realdash.net/cotech/32/8_2.png) [@CoTECH](https://forum.realdash.net/u/CoTECH)\ **Post date:** [October 6, 2019, 7:15pm UTC](https://forum.realdash.net/t/usb-serial-not-connection-on-android/159/13 "2019-10-06T19:15:18Z")
> [@](#): > > Could you be using non-arduino device that has big endian processor? So you speak for android? Or for what? ---
**Author:** ![CoTECH](https://forum.realdash.net/user_avatar/forum.realdash.net/cotech/32/8_2.png) [@CoTECH](https://forum.realdash.net/u/CoTECH)\ **Post date:** [October 6, 2019, 7:15pm UTC](https://forum.realdash.net/t/usb-serial-not-connection-on-android/159/14 "2019-10-06T19:15:59Z")
Totally confused? How furious this translator is! ---
**Author:** ![CoTECH](https://forum.realdash.net/user_avatar/forum.realdash.net/cotech/32/8_2.png) [@CoTECH](https://forum.realdash.net/u/CoTECH)\ **Post date:** [October 6, 2019, 7:58pm UTC](https://forum.realdash.net/t/usb-serial-not-connection-on-android/159/15 "2019-10-06T19:58:19Z")
Another point surprises me. My android tv box is an x86 architecture that essentially works with memory in little -endianess order. Arduino also conveys information like little endianess. It turns out these devices must fully understand each other. And there should not be conflicts. Isn’t it easier then to make RealDash flexible with the ability to choose byte order? ---
**Author:** ![CoTECH](https://forum.realdash.net/user_avatar/forum.realdash.net/cotech/32/8_2.png) [@CoTECH](https://forum.realdash.net/u/CoTECH)\ **Post date:** [October 7, 2019, 1:06pm UTC](https://forum.realdash.net/t/usb-serial-not-connection-on-android/159/16 "2019-10-07T13:06:51Z")
Hurrah. I figured it out. Arduino is not a problem. Everything worked. With direct byte order))))