Chess Table

We needed a coffee table for our new house but had yet to find the right thing. I found this tired black circular table outside a neighbour’s house and was inspired to create a nice top for it.

Whitterm-220 Clever Serial Terminal

The Whitterm-220 (WT-220) is my latest project. It’s a clever terminal, in the sense that it aims to emulate the dumb terminals of the 80s but with the versatility of something produced now. The name comes from my inspiration for the project: failure to win a VT-220 on eBay. I decided it would be fun to make a homage to the VT-220, that would actually be useful – a not so dumb, or clever terminal – that would do more than simply parsing RS232 levels into Ascii characters.

Continue reading Whitterm-220 Clever Serial Terminal

Nixie Tube Energy Meter

Featured on Hack a Day

Having recently bought a house, project time has been a bit thin on the ground. As a standard terrace house, the consumer unit and electricity meter were in the entrance hallway, exposed and looking a bit naff. I liked the look of the meter so I quickly created a box that allowed the meter to poke through and leave access to the fuses.

The box covering did the job but felt a bit cumbersome with all that spare space; it needed something else to give it more purpose. An energy meter was the obvious thing but I didn’t want a garish LCD or 7 segment display, it need to match the blown glass electricity meter… …nixie tubes!

The Nixie Module runs off 5V and SPI
The Nixie Module runs off 5V and SPI making the project quick to get off the ground

Continue reading Nixie Tube Energy Meter

Setting Wooden Bits via BLE and ESP8266

My laser cut binary clock, Wooden Bits, originally had no means to set the clock, other than at compile time. I later added a tactile button and ISR to provide this function (increment the time until the correct time is shown) but I wanted a way to tap into the extra features of the DS3231 (alarm, temperature) and also to experiment in wireless control.

Continue reading Setting Wooden Bits via BLE and ESP8266

Raspberry Pi DAC – MCP4725 with wiringPi

The Raspberry Pi lacks a DAC but using the I2C bus, one can easily add a device like the 12bit MCP4725. The GPIO library wiringPi provides support for I2C devices, however, getting the MCP4725 working with it isn’t a simple as one might hope. The device is 12bit but the I2C protocol works on bytes (8bits). To send 12bit data, the Microchip designed the message transfer like this:

The MC4725 expects the 12bit data to be broken into two bytes and sent directly after each other.
The MC4725 expects the 12bit data to be broken into two bytes and sent directly after each other.

Continue reading Raspberry Pi DAC – MCP4725 with wiringPi