MiniPiio PCB board’s arrive at last !

June 22, 2012

Exciting times are here.

We received our first batch of PCB’s from our manufacturer yesterday.

In the package were 5 sets of blank PCB’s for the RPi_ProtoBoard and the first of the MiniPiio boards: MiniPiio_RS232, MiniPiio_DIO16, MiniPiio_ULN2803 and MiniPiio_ProtoBoard.

Even though it was late at night we couldn’t resisting building a couple of the boards. So we built the RPi_Protoboard:

and the MiniPiio_ProtoBoard:

hers a picture of both boards:

We’ll get the rest of the boards assembled over the weekend and post them here.

Arduino PLC v0.20

June 27, 2010

The design for the Arduino PLC shield is coming together now.

I’ve removed the “flywheel” diodes from the relays as the ULN2803 already has them. I’ve added a simple +5V power supply and changed the Arduino footprint to the Seeedstudio clone so we get an extra two analog inputs. The standard Adrunio Duemilanove will work as well but you won’t get the extra two analog inputs. I don’t think the TLP521 can sink sufficient current to illuminate the input LED’s so I might added some transistors to do that or just remove the input LED’s completely.

The updated schematic is here:

arduino_plc 0v20

Arduino PLC Shield Schematic v0.10

May 24, 2010

I’ve managed to find some time this week to put together a draft schematic for the PLC shield.

I’ve only included 4x opto isolated inputs as I happened to have some TLP521 Quad Opto’s handy. I’ve added a couple of extra analog inputs as I may used a Seeedstudio v2.12 Arduino clone and that has an extra two analog pins so it makes sense to have them available and I’m still need to find a spare control signal to control the RX/TX enables for the RS485.

arduino_plc 0v10

An update can be found here:
Arduino PLC v0.20

XArduino – A 400-MIPS co-processor for Arduino

February 7, 2010

Recently I’ve been working on XArduino which is a XMOS XS1 L1 co-processor for the Arduino open-source electronics prototyping platform.

The XArduino board provides Arduino applications with a 400 MIP’s multi-threaded 32-bit co-processor, as well as providing a VGA video output and PS/2 keyboard/mouse input for Arduino application.

It features a standard XTAG-2 to for programming and debugging. In addition the XTAG-2 interface will allow for XK-1 boards to access the VGA and PS/2 interfaces as well as way of connecting standard Arduino shields.

Note: This is a 3.3V-only board

The project is hosted at

Creative Commons Attribution-ShareAlike 3.0 License

Zuzebox – at last the PCB is started

November 15, 2009

I finally found some time to start the PCB for Zuzebox (a Uzebox compatible retro-minimalist homebrew game console). I’m hoping to squeeze it all into a 100mm x 100mm board so I can use Seeedstudio’s Fusion / Propaganda PCB service. The picture below only shows about half the components laid out, so I think the final PCB is going to be busy.

Zuzebox - starting PCB layout

List of Arduino compatable CPU boards

April 24, 2009

Jeff Saltzman has compiled a good list of Arduino compatable CPU boards. It can be found on his blog.

Another good list on all things Arduino can be found at

Arduino – bringing hardware back to the masses

April 3, 2009

The Arduino project is another AVR based project that’s caught my attention. Quoting from the Arduino site

“Arduino is an open-source electronics prototyping platform based on flexible, easy-to-use hardware and software. It’s intended for artists, designers, hobbyists, and anyone interested in creating interactive objects or environments.”

Although the Arduino system and software has been around for a couple of more years it has really gained in popularity over the last year. Logging onto their Forum shows over 10,000 registered members.

The current basic design Duemilanove is based on a Atmel ATmega168 Microcontroller, clocked at 16Mhz with 16K Flash memory, 1KB SRAM and 512-bytes EEPROM for the ATmega168 or 32KB Flash memory, 2KB SRAM and 1KB EEPROM for the ATmega328 variety. The 2.1″ x 2.6″ (51mm x 73mm) PCB has 14 Digital I/O Pins (of which 6 provide PWM output and others can provide UART, SPI or I2C functions) and 6 Analog Input Pins.

Like any good idea, Arduino has provided inspiration for others and there are many other “Arduino” compatible or similar boards to choose from such as Freeduino, Boarduino and Seeeduino.

For me, Arduino invokes the spirit of the 1970’s where the early computer hackers, pioneers and developers shared their knowledge for the greater good of the computing community (who knows could we see a new Bill Gates emerging – OK perhaps not as rich).