March 25, 2013

MSX emulatation on MK802

In this post i show how to install openMSX on MK802 running running a lubuntu 12.04 image from

Open a terminal and install the openmsx-catapult package by typing:

sudo apt-get install openmsx-catapult

This will install all the needed packages. openMSX Catapult is a GUI to configure and launch the openMSX emulator. Start it by typing:


Select a game ROM file under Cart A then press the Start key to start the emulation. With the default MSX type there is no need for a bios file. But for other types it will be needed. Below i have installed a bios file from Spectravide SVI-728.

If you have an USB game pad connected to your MK802 go to the Misc Controls tab and select joystic1 as Joystic port 1.
 When the emulaton is running you can enter fullscreen mode with the F12 key

March 13, 2013

Energia a port of Arduino IDE for TI MSP430

Energia is a port of the Android software for the TI MSP430 LaunchPad. My LaunchPad with a MSP430G2231 has mostly been collecting dust lately so i decided to give it a try. My first test was the provided blink a LED and serial communication examples and as expected they worked fine. So I decide to try something a little more challenging.

I installed my library from the previous post and hit compile. There was no errors but the pin assignment needed to be updated for the MSP430. I did the changes below and downloaded it to the LaunchPad.
const int loadPin  = P1_4;
const int sdataPin = P1_5;
const int sdclkPin = P1_7;

As you can see in the picture below it worked. Energia is a promising software. The latest version on the web page is a bit old but the git repository seems to be updated lately and the forum is quite active so hopefully the work will continue.

March 6, 2013

Arduino library for Osram SCDQ554xx Displays

This is a description of my Arduino library for Osram SCDQ554xx Displays. The library is available for
download here. For installation instructions see my older post Installing newping library.

The device that I have used is the SCDQ5542Q. But the following devices should also be supported:
  • SCDQ5541X (Yellow)
  • SCDQ5542X (Super-red)
  • SCDQ5543X (Green)
  • SCDQ5544X (High Efficiency Green)
The display is a tiny LED display with 4 characters with a 5x5 Dot Matrix. The device has no built-in character definition instead each dot is individually programmed to be on or off.

My libray has an example with the numbers 0-9 and decimal point defined. Other symbols can easily be added. For character sets and other details see the Data sheet. 

March 3, 2013

Review of Arduino Ethernet Shield W5100

You have probably seen the non official low cost Arduino Ethernet Shield from China or Hong Kong with the WIZnet W5100 chip that you can get for about $10. So are they any good? I ordered one to see. It arrived intact after a month packed in a solid cardboard box but without any ESD protection.The build quality seems to be good.

I loaded the WebServer example and hooked it up to my network and it worked immediately without any problems.

I also tested the SD card interface with two of the examples provided by the Arduino software. The first test was with the SD card basic file example (files).
The second test was SD listfiles example. Note that you need to edit this example to run it with the Ethernet shield since it is written for usage of pin 10 instead of pin 4. Simply search for "SD.begin(10)" and replace it with  "SD.begin(4)". Below is the result with a card from an old Android phone.
When buying the Shield it is advertised to have the MAC address: 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED (Note the hacker humor "dead beef feed") but this is not true since it set by your Arduino code. Sure this is the default value for MAC address in the examples but you can set it to whatever you like. If you have multiple devices on the same network it is probably a good idea to set it unique for each devices since the router might be confused otherwise.

+ Low cost.
+ Works with the SD and Ethernet examples in the Arduino software (Tested with 1.0.3).

- You are not supporting the creators of Arduino but the design is open source so anyone can build and sell them legally.