Monday, June 20, 2011

Development board for 18F4550

I have designed a simple development board for 18F4550 to test my projects.I'm using a bootloader to program the uC using USB.It's very easy and fast for doing projects.I'll tell about it in next post.

You can easily build this circuit on a veroboard or a PCB.

This is my completed circuit on a veroboard.

Friday, June 17, 2011

Very simple PIC 18F programmer

I was wondering to use some PIC 18F microcontrollers in my projects.The well known 18F2550 & 18F4550 got USB which is much useful in current environments.But the problem was didn't have a good programmer to program them.My intention was to build a good USB programmer like PICKIT2lite but it also need a 18F2550 which should be programed in order to use this.So,I was looking for a very simple and easy to build programmer for 18F.Luckily I was able to find such,called ART2003 programmer.It just needs a 220 Ohm resistor,a 47uF capacitor and some 1N4148 diodes.All these parts are available at any part of the country.The total cost for this project was below Rs:100/=

Here's my little programmer :)

The schematic can be found at:
Fox Delta

I use WinPIC 800 v3.59 which also can be found on that link to program the microcontroller.Make sure you have enabled Low Voltage Programming(LVP) fuse.
You have to connect PGM,PGC,PGD,MCLR,VDD,VSS pins according to your uC's datasheet.

Now I can build my own PICKIT2lite USB programmer :)
You can also use this simple programmer to programmer a Bootloader and then you can change the program on microcontroller without any programmer by just using USB.

Tuesday, June 14, 2011

Sinhala support on Android

Android has become the OS which powers many smart phones.But as it lacks built in Sinhala support,we have to add it by our own.Even these steps gives you a partial sinhala support in your mobile,the text won't be rendered well in most places.
Currenty,we have partial or full support on following;

1.Sinhala text displaying
2.Sinhala text input
3.Sinhala web browsing

For Sinhala text display in any app,you have to install a Unicode font with Sinhala support,basically you have to replace DroidSansFallback.ttf font in /system/fonts with Sinhala unicode font.(Your mobile has to be rooted for this and there are number of guides on the internet.Just "Google" about your mobile phone rooting.)These are wonderful guides on how to do this.

Kalinga's blog post
GayanX86's blog post

Now you got the "Sinhala text displaying" in your mobile.

There is no input method for Sinhala,hence I've created custom layout based on Wijesekara keyboard layout and submitted it to hackerskeyboard app development team.With there support now it's available on hackerskeyboard v1.16rc3 and above.You can get it from(or android market itself later),

Please note that "Rakaranshaya" and "Kombuwa" is not working yet.If you are an android developer please try correct that problem.

Here are some screenshots of the input:

Even though now you can view sinhala webpages,it lacks proper rendering,There is an great app created by Dhanika,which can render Sinhala in webpages.You just have to install it.

Hope you will able to get Sinhala support on android,if there is any prob please put a comment.I will post more about the input development.