# Error in UART communication between Uno & Nano **URL:** \ **Category:** Uncategorized\ **Created:** [August 7, 2018, 4:41pm UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024 "2018-08-07T16:41:16Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![antonzlo](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.xod.io/antonzlo/32/461_2.png) [@antonzlo](https://forum.xod.io/u/antonzlo)\ **Post date:** [August 7, 2018, 4:41pm UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/1 "2018-08-07T16:41:16Z")
Hello! I made a project, but Uno’s pins have ended. I wanted to add a Nano and make it communicate with each other via UART, but unsuccessfully. What is wrong? Codes are here. [receive.xodball](https://canada1.discourse-cdn.com/flex027/uploads/xod/original/1X/010425f530c1a67a9501f45c53729c8d108a1e85.xodball) (3.1 KB) [transmitt.xodball](https://canada1.discourse-cdn.com/flex027/uploads/xod/original/1X/7e54365f6e63a5e542905073f274972869b8861a.xodball) (4.8 KB) ---
**Author:** ![s7ven](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.xod.io/s7ven/32/447_2.png) [@s7ven](https://forum.xod.io/u/s7ven)\ **Post date:** [August 21, 2018, 4:06am UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/2 "2018-08-21T04:06:52Z")
For a start, you haven’t called “begin” on the UART at boot. This gets the ball rolling. ---
**Author:** ![antonzlo](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.xod.io/antonzlo/32/461_2.png) [@antonzlo](https://forum.xod.io/u/antonzlo)\ **Post date:** [August 22, 2018, 11:40am UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/3 "2018-08-22T11:40:22Z")
Do i need to begin it on both Arduinos? ---
**Author:** ![antonzlo](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.xod.io/antonzlo/32/461_2.png) [@antonzlo](https://forum.xod.io/u/antonzlo)\ **Post date:** [August 22, 2018, 1:09pm UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/4 "2018-08-22T13:09:31Z")
So? [receive.xodball](https://canada1.discourse-cdn.com/flex027/uploads/xod/original/1X/1a44b4ffa2f89c0565e69b266996af37e87bb8da.xodball) (3.5 KB) [transmitt.xodball](https://canada1.discourse-cdn.com/flex027/uploads/xod/original/1X/2ea185049416d6b9550b4247598cd88effa761e5.xodball) (4.2 KB) ---
**Author:** ![tobias](https://avatars.discourse-cdn.com/v4/letter/t/c67d28/32.png) [@tobias](https://forum.xod.io/u/tobias)\ **Post date:** [August 22, 2018, 6:34pm UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/5 "2018-08-22T18:34:16Z")
Look at this, @nkrkv is about to write a guide on this. Maybe you can help each other. > [@What is the best example for UART/Serial guide article?](https://forum.xod.io/t/what-is-the-best-example-for-uart-serial-guide-article/1010): > > Hello everyone! I’m thinking about writing down a bunch of guide/recipe articles and showing UART (aka serial) communication should be one of them. However, while planning the article structure I can’t come up with a “right” example for UART. The right example should use some ubiquitous hardware, serve a clear and useful purpose, do not involve other complex topics other than UART communication. I remember such tutorial was requested several times on the forum. So I’m asking for an advice: wha… ---
**Author:** ![s7ven](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.xod.io/s7ven/32/447_2.png) [@s7ven](https://forum.xod.io/u/s7ven)\ **Post date:** [August 22, 2018, 9:09pm UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/6 "2018-08-22T21:09:51Z")
Yes. It sets the baud rate for communication. Serial comms won’t work without that being correct. ---
**Author:** ![antonzlo](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.xod.io/antonzlo/32/461_2.png) [@antonzlo](https://forum.xod.io/u/antonzlo)\ **Post date:** [August 24, 2018, 12:16pm UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/7 "2018-08-24T12:16:12Z")
Can i use I2C if i couldn’t make a connections? ---
**Author:** ![nkrkv](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.xod.io/nkrkv/32/8_2.png) [@nkrkv](https://forum.xod.io/u/nkrkv)\ **Post date:** [August 24, 2018, 2:22pm UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/8 "2018-08-24T14:22:21Z")
UART guide article is coming next week. The author is not me, but nevertheless, it will shine the light on serial communication I hope. ---
**Author:** ![s7ven](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.xod.io/s7ven/32/447_2.png) [@s7ven](https://forum.xod.io/u/s7ven)\ **Post date:** [August 24, 2018, 11:33pm UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/9 "2018-08-24T23:33:32Z")
Why don’t you make a simple transmitter using the arduino IDE, from an example or similar. Something you know works.? Then use XOD to make a simple patch that listens for received bytes. This would be to establish you can make at least a connection (You may have a damaged board or something). One thing I noticed when I was playing around with the uart library is that in the soft-uart patch code, when the SoftwareUart class is instantiated, the call to the software serial has the tx and rx parameters reversed. It should be \_serial(tx, rx). ---
**Author:** ![antonzlo](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.xod.io/antonzlo/32/461_2.png) [@antonzlo](https://forum.xod.io/u/antonzlo)\ **Post date:** [August 26, 2018, 6:45pm UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/10 "2018-08-26T18:45:52Z")
> [@s7ven](#): > > (You may have a damaged board or something). I have noticed, that my board have a problem reading ds18b20… About Arduino IDE, I just wanted to do it in XOD, but I will try. How about I2C? Is it only for sensors or displays, ets? Can I do a “phone” for arduino using it? ---
**Author:** ![s7ven](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.xod.io/s7ven/32/447_2.png) [@s7ven](https://forum.xod.io/u/s7ven)\ **Post date:** [August 26, 2018, 9:58pm UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/11 "2018-08-26T21:58:39Z")
I’m only suggesting the Arduino IDE as part of the problem-solving process. At this stage, you don’t know if your client code, your server code, the XOD IDE code, or the hardware itself which is the issue. So best to eliminate as many variables as you can. I haven’t used I2C for comm devices, so can’t help there. I’m currently using an HC-12 with the UART library. ---
**Author:** ![antonzlo](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.xod.io/antonzlo/32/461_2.png) [@antonzlo](https://forum.xod.io/u/antonzlo)\ **Post date:** [August 28, 2018, 4:48pm UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/12 "2018-08-28T16:48:56Z")
I am testing now with Ide and i understood that i did not connected grounds together… I am idiot ---
**Author:** ![antonzlo](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.xod.io/antonzlo/32/461_2.png) [@antonzlo](https://forum.xod.io/u/antonzlo)\ **Post date:** [August 28, 2018, 5:00pm UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/13 "2018-08-28T17:00:49Z")
All work with softwareserial library will try in xod with ground:) ---
**Author:** ![antonzlo](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.xod.io/antonzlo/32/461_2.png) [@antonzlo](https://forum.xod.io/u/antonzlo)\ **Post date:** [August 28, 2018, 5:19pm UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/14 "2018-08-28T17:19:12Z")
I can’t do it… ☹ receiving Arduino just don’t switch 13 led off from starting… but also i will try I2C ---
**Author:** ![s7ven](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.xod.io/s7ven/32/447_2.png) [@s7ven](https://forum.xod.io/u/s7ven)\ **Post date:** [August 29, 2018, 6:10am UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/15 "2018-08-29T06:10:42Z")
Mistakes are how you learn. The more mistakes the more you learn. ---
**Author:** ![antonzlo](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.xod.io/antonzlo/32/461_2.png) [@antonzlo](https://forum.xod.io/u/antonzlo)\ **Post date:** [September 5, 2018, 2:18pm UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/16 "2018-09-05T14:18:11Z")
i have tried in XOD, but unsuccessful… ---
**Author:** ![s7ven](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.xod.io/s7ven/32/447_2.png) [@s7ven](https://forum.xod.io/u/s7ven)\ **Post date:** [September 5, 2018, 9:56pm UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/17 "2018-09-05T21:56:13Z")
What is the arduino code and what is the XOD patch you tried? ---
**Author:** ![tobias](https://avatars.discourse-cdn.com/v4/letter/t/c67d28/32.png) [@tobias](https://forum.xod.io/u/tobias)\ **Post date:** [September 11, 2018, 6:41am UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/18 "2018-09-11T06:41:17Z")
Hi @nkrkv, any news on the UART guide? Best Tobias ---
**Author:** ![nkrkv](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.xod.io/nkrkv/32/8_2.png) [@nkrkv](https://forum.xod.io/u/nkrkv)\ **Post date:** [September 13, 2018, 4:29pm UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/19 "2018-09-13T16:29:04Z")
Ah, sorry, it is late because we were too busy preparing the new release. We’ll return to the guide in the nearest days. @gabbapeople already have a working prototype and an almost ready article content. ---
**Author:** ![antonzlo](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.xod.io/antonzlo/32/461_2.png) [@antonzlo](https://forum.xod.io/u/antonzlo)\ **Post date:** [September 13, 2018, 4:51pm UTC](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024/20 "2018-09-13T16:51:06Z")
@nkrkv working prototype? Sounds good 🙂 [Next page](https://forum.xod.io/t/error-in-uart-communication-between-uno-nano/1024.md?page=2)