Little updates today

Updated the SMD OVEN with PCB vs 1.2, removed some old projects from menu (if interested anyway you can found them link when you click on ‘Electronic project’)

I was thinking to build a small Multiboard (only micro & minimal electronics) what you think?

74181 ALU design on Altera MAX II CPLD


Dilshan Jayakody writes:

74181 is 4-bit arithmetic and logic unit introduced by Texas Instruments in March 1970 and it is known for being the first ALU in single package. This chip is no longer in manufacturing but still it is quite popular in CA (computer architecture) courses in many colleges.
To test the behavior of this 4-bit ALU we decided to construct it on Altera MAX II CPLD. For this project we choose EPM240T100C5 CPLD and logic design is implement using Altera Quartus II. For logic design we refer Fairchild Semiconductor’s DM74LS181 datasheet. This setup is tested on basic EPM240 series development board with some mechanical switches and couple of LEDs.

Project info at Jayakody’s blog and elect.wikispaces.com.

Source: DP

Apple II ROM Dumper


Quinn Dunki created an Apple II ROM tool project and posted a great write-up on digging into the ROM of her Apple IIc Plus:

You may recall way back when I started my Apple II ROM Tool project, that I had intended to fix some bugs. That was the whole point of this adventure. It took a bit longer than I expected to get here, but we can finally put our kilohertz where our mouth is and fix some brokeass code. But wait, you might be asking, what bugs are in the Apple II ROM? It’s code that shipped in millions of machines, and had hundreds of thousands of pieces of software built around it. What bugs could there be? Well, sometimes a bug is in the ear of the beholder.

See part 1 and part 2 here.

Check out the video after the break.

Source: DP

App note: A microwatt charge pump boosts 1 V to 1.8 V at 90% efficiency, providing “Always On” standby power for microcontrollers


Silicon Labs’ app note featuring low power boost for microcontrollers. Link here (PDF)

Boosting the output voltage of common alkaline button-cells to at least 1.8 V needed by microcontrollers provides an “always on” standby power source sufficient for low-power oscillator interrupt/sleep state operation. Two ultralow power op amps are used in a charge pump configuration to double an input voltage, creating an output voltage of approximately 2x the input voltage. Output currents up to 100 µA are available at 90% efficiency; even load currents as low as 10 µA achieve 80% efficiency, beating commercially available charge pump ICs and inductorbased boost regulators.


Source: DP


Feeds Problem

After a few months of operation, the plugins for RSS is unusable, I’m looking for a replacement, if you have suggestions, please let contact me