Friday, November 7, 2014

ESP8266 possible breadboard interface

Probably you know what the ESP8266, if not it is a very cheap Uart to Wifi module (more info). Anyhow to the important part.
This module is 3.3V and my Arduino is 5V. There is a problem. Also the module is not "breadboard friendly".
So there are two problems that a simple interface board can fix very easy. Based on that, I have a few ideas running in my head about this. I am in the process of designing a board that I would like to build a prototype.
What this magic board do?
1. Voltage regulator, IN 5V and regulate to 3.3V with 3.3V output as well.
2. Level shifter for RX and TX signals, so you can wire it up straight to the arduino.
3. Bread board friendly header pins for easy testing.

This is a very small design to keep it cheap. As is of now it is 1 inch by 1 inch. It is not in its final stage, however I like to write about it, just in case.

pcb board



schematic

I will continue on improving the design for a bit more. However I want to try to actually build it, however build time for me is very limited now, so only time will tell how this gets done.

All eagleCad files are here. This is very early in the design process. I have started two times, and probably restart it all again.

Any idea or comment, please do. This is public domain, so you may do what ever you want with it. If you build it as is or modify it, comment about it and post pictures. There is no need to mention or link back to me.

Update:
Board modified a little bit and sent to oshpark for a prototype. Soon will know if it actually works.
Eagle files moved to a github repo of it's own here. Now the board has a name it is called WifIco (it needed a name you know).

This is the image rendered by OSHPark web site when ordered.

Bottom View Top View


This has not been tested however I decided to order it anyhow. It has a mini usb port beneath only for 5V input. Just in case I wanted to power it stand alone, who knows!
It also has two resistors visible on the bottom view, that should be soldered shut for normal use. You may solder a wire or a zero resistor, actually whatever you have. They are pull up and can be shut. I figure that since I will be receiving a few boards may find it useful to use one to update the firmware and in those cases I would need access to the pins exposed there. But for normal operations I may not. 

Update:
This design has a lot of errors in the silk screen for the board connections. It worked, but the labeling of the connections is incorrect.




Thursday, October 2, 2014

Adding .gitignore file after first repository commit

It happen to me very often to create a git repository and even push it to mu github without first creating a .gitignore file. Specially on Android projects this publishes a lot of unwanted files, like binary and temporary files. For this I found a post on stackoverflow for just that.

From all the post I read this is the one that worked for me (at least now)
http://stackoverflow.com/questions/7927230/remove-directory-from-remote-repository-after-adding-them-to-gitignore

I did this, however in the post is more information about it, please go to the stackoverflow link and if it work for you go ahead a plus it.
git rm --cached `git ls-files -i --exclude-from=.gitignore` 
git commit -m 'Removed all files that are in the .gitignore' 
git push origin master

If you have a better way to do this please leave a comment.

Thursday, July 17, 2014

Note to future self

Today is a regular day of July 2014 with the exception that I am writing a few lines for my future self.
These days the technology is moving very fast. Everyone has or want what is called a smart phone. The market is dominated by Apple iPhone and Google Android. In a not so close third place there is Microsoft with the windows phone.
Apart of phones home electronics is getting everyday more strong.
Just wanted to tell myself that no matter how cool technology may be there are other things more important. As am engineer we need to understand that at the other end of any software or hardware there is a person.  Is on those humans that we need to think.
When you read this,  Samsung may not have any galaxy phone but there will be people and your family will be at your side.
Keep what is worth, there is no undo checkout for missing life moments. Today I am a happy person and for sure in the future will still be.
The crime is worst every day like the economy.  We are holding up for better days to come. Always happy and together with the family.