NOTE: Some parts of this excellent guide have become outdated after a change to the forum software. For an updated guide, see:
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1. Register and sign in
Create an account (if necessary), and login (sign in).
2. Choose an appropriate forum section
Browse through the forum sections (not all shown) and choose the most appropriate one (some suggestions highlighted):
3. Choose the correct language
The initial sections are for posting in English. If you want to post in other languages scroll down to find an appropriate one (some suggestions highlighted):
4. Do some research before posting
Try to solve your problem, or answer your question, yourself. For example, if you are wondering how to connect LEDs to a 74HC595 register, try Googling exactly that (add the word "Arduino" to narrow things down):
The above example gave lots of hits. Read some of them, perhaps your question has already been answered.
If you don't bother doing that, and if your question shows no indication you have tried to help yourself, you may find people doing it for you:
If that doesn't help, try browsing existing threads in the forum for a while. Maybe what you are asking is currently under discussion in another thread.
Tip: If you want to just search this forum, use the Google "site" specifier, for example:
motor power site:arduino.cc
5. Click on the New Topic button
Click the button shown: "New Topic"
6. Make a meaningful subject line
Try to summarize your problem with a helpful and informative subject line. Helpful subjects draw in people who might know the answer. Unhelpful ones are likely to be skipped.
Examples of unhelpful subject lines:
- Noob here, help needed
- Help me, quickly!
- Got error
- Lost, help me
- Problem with my circuit
- No idea what I am doing
Example of a good subject line:
In particular avoid subject lines in ALL CAPITALS. That annoys a lot of people, they feel as if you are shouting at them.
7. If you are posting code or error messages, use "code" tags
For code, error messages, program output, etc. select the code, and click the "Insert code" button, as shown
This makes the code much more readable, and also stops things like the following turn the entire rest of your post into italics:
a = b [i];
After you have clicked the "Insert code" button you will see code tags around your code and messages, like this:
(In that example I highlighted both the code - and clicked the "</>" button - and then the error message - and clicked the button again).
If you click the "Preview" button under your post you'll see what the code tags have done, and can check everything looks OK before posting:
8. You can add attachments
If your code is too long to fit into a post, or you have multiple files (eg. code and libraries), or you want to show an image, click on the Additional Options button:
Then you can browse your hard disk for the image, code, schematic, photo, that you want to attach.
Please resize photos down to a reasonable size. A 4 megabyte photo takes a long time to download. As a courtesy to other forum users, images should be no more than a couple of hundred K bytes.
9. You can insert images
If you have an image hosted on your own (or a public) site, you can imbed the image directly inside the post, for example:
Paste your image URL between the "img" tags:
10. Post in proper sentences
This is a forum you are using, not a mobile phone.
As a courtesy to the people you are hoping to have help you, type complete sentences. That is:
- Start with a capital letter.
- Spell words properly.
- Finish with a period (full-stop). (Just the one, thanks!)
For example, instead of:
i need ur help with my code i dont no what i did wrong pls answer quick i am such a noob thx
This is much better:
Hi! Can you please help me with my code? I attach a copy below.
Code pasted here inside code tags.
I got these error messages:
Errors pasted here inside code tags.
Any help appreciated. Thanks.
Taking the time to make a proper, punctuated, post is a mark of courtesy and respect. It will improve your chance of a response.
11. Tips for getting the most out of your post
- Mention which Arduino you have. Is it a Uno? Leonardo? Due? Mini? Mega? The problem might be specific to a certain model.
- Describe your problem in detail.
- If it relates to an electronics part (chip or board), give the exact part number and preferably a link to the data sheet.
- Describe how you have connected things like switches. Are they wired to ground? Or +5V? Are there pull-up or pull-down resistors? Post a circuit if there is doubt.
- Post a complete sketch (program code)! If you don't you waste time while people ask you to do that. However, with coding problems, if possible post a "minimal" sketch that demonstrates the problem - not hundreds of lines of code. If the problem goes away in the minimal sketch, it wasn't where you thought it was.
- Copy and paste code. Don't retype "from memory" on your mobile phone, in the train.
- If you get an error, post the error (copy and paste). Not just "I got an error".
- If you have debugging information in your sketch, post your debugging displays.
- If you are using a library that does not come with the IDE (in other words, you downloaded it from somewhere) please post a link to this library.
- Describe what you expected to happen, and what actually happened. Not just "it doesn't work".
- If possible, describe what you are really trying to do, not what you think might work. For example "I am trying to turn on an aquarium heater and pump at the same time", not "how do I break out of an interrupt?".
- Try to narrow down the problem, whether coding or electronic. Don't confuse us and yourself by trying to do everything at once. For example, if you are having problems reading a sensor, make up a simple test case, that tests that sensor (both electrically and in code).
- Put your location (country) in your forum profile. That allows answers to better help you with mains voltages, local suppliers, and other local issues.