Saturday, April 18, 2015

Connect ATmega328 with HC-05 (ZS-040) Bluetooth module

Parts list

  • ATMega328 (I use handy Arduino Nano);
  • HC-05 (ZS-040) Bluetooth module (EGBT-045MS);
  • 1K Ohm and 2K Ohm resistors;


HC-05 or ZS-040 Bluetooth module is based on EGBT-045MS chip and has following pins on board:
  • STATE - HIGH when module is connected;
  • RXD - data input pin;
  • TXD - data output pin;
  • GND - ground pin;
  • VCC - power input pin;
  • EN - Unknown pin. It should be connected to pin 34 of EGBT-045MS Bluetooth module, but it seems it doesn't work in preferred way;

Saturday, March 28, 2015

How to upgrade Django 1.6 to Django 1.7

  • Update django package:

    pip install -U Django
  • Remove 'south' from INSTALLED_APPS.
  • Delete all your (numbered) migration files, but not the directory or - make sure you remove the .pyc files too.
  • Run python makemigrations. Django should see the empty migration directories and make new initial migrations in the new format.
  • Run python migrate. Django will see that the tables for the initial migrations already exist and mark them as applied without running them. (Only matching table names are checked; not their full schema
  • it’s up to you to make sure the existing schema is up to date with your models!)
  • Uninstall south package:

    pip uninstall south
  • Update requirements.txt file:

    pip freeze > requirements.txt


I'm using a great Python hosting - Webfaction. So here is short notes how to upgrade existing deployed application to Django 1.7.

  • Create new application with Django 1.7
  • Copy project folder from old Django 1.6 application to new Django 1.7 application.
  • Modify httpd.conf accordingly with new folder structure.
  • Stop existing existing application with django 1.6.
  • Restart new django 1.7 application:

  • Remove django 1.6 from Websites-> -> Contents.
  • Add new django 1.7 app to Websites-> -> Contents.

Done. Check how it works.

PS: And don't forgot to update fabric deployment file accordingly.

Friday, March 20, 2015

How to set up and run unit tests in ClojureScript

This tutorial covers initial setup of a development environment to run unit tests in ClojureScript project.

Thursday, March 5, 2015

Vimium - Hacker's browser

Vimium is Google Chrome and Chromium extension, which brings Vim-like navigation to your browser. You can install it from Chrome Web Store or from a source code.

Friday, February 13, 2015

Countries list in JSON format

In my previous post I shared the list of US State, but in comments followers asked about the list of countries. So here is the list of 252 countries with ISO codes as abbreviation in JSON format: