Obstacle avoiding car not working properly

[rishudoespvp]

Hi, i am trying to make a obstacle avoiding car using Arduino UNO and Motor driver L293D and i have uploaded the code and the libraries and i am using a 9v battery when i upload the code its starts working and works fine(while the plug is still connected to arduino) when i take out the plug it stops working even if the battery is connected i don't know why but everything is fine still its not working please help me regarding this

[Idahowalker]

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Help us help you.

Please follow the advice given in the link below when posting code, in particular the section entitled 'Posting code and common code problems'

Use code tags (the </> icon above the compose window) to make it easier to read and copy for examination

How to get the best out of this forum

See also FAQ - Arduino Forum for general rules on forum behavior and etiquette. Hello, Welcome to the Arduino Forum. This guide explains how to get the best out of this forum. Please read and follow the instructions below. Being new here you might think this is having rules for the sake of rules, but that is not the case. If you don’t follow the guidelines all that happens is there is a long exchange of posts while we try to get you to tell us what we need in order to help you, which is frus…

Use the IDE autoformat tool (ctrl-t or Tools, Auto format) before posting code in code tags.

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If you are using a 9V battery like this.

Don't.

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Info about multi things

Demonstration code for several things at the same time

NOTE for newcomers. The demo is entirely contained in this Post and Reply #1. There is no need to read further unless you are interested. ...added 25Sep2014 There have been a few occasions recently where newcomers seemed to have difficulty applying the "blink without delay" and "state" concepts to a sketch that is intended to manage a number of concurrent actions. Its very time consuming to respond with suitable code examples - particularly as every case is a little different. I have prepared…

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I2C scanner

https://www.arduino.cc/reference/en/libraries/i2cscanner/

How to Scan and Detect I2C Addresses

What did the I2C scanner report?

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Bread board power rail split

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Serial Input basics.

Serial Input Basics - updated

Updated Version Please note that this is a revised version of the advice in this earlier Thread which has become very long. As far as possible I have kept the code examples identical or simplifed them slightly. It should not be necessary to refer to the older Thread, but feel free to do so. Contents The following sections are in this Tutorial Introduction Serial data is slow by Arduino standards Example 1 - Receiving single characters Why code is organized into functions Exampl…

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The search box is a useful tool.

For instance using the words "9v battery" in the search box one could find lots of reasons why this may be a bad idea.

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disclaimer

The events portrayed in this post are not all true. The names are not real names of real people and real organizations.
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