The Akafugu Nixie Clock

I like Nixie tubes, especially when they are used in clocks, like this one I built a while ago. Although almost all Nixie clocks look the same, sometimes there is one that catches the eye. Such as the case of Agafuku Nixie Clock, designed in (and shipped from) Japan. The first thing to notice is that the final clock built from this kit is complete with enclosure, a rare find in the world of Nixie clock kits. Then, there is the look: simple, yet elegant, compact, yet functional. Obviously, I wanted one. Per, from Akafugu Corporation, graciously accepted to barter their Nixie clock kit for my Wise Clock 4 kit. Following is my brief review.


The Akafugu Nixie clock kit looks professional starting with the box. Here are a few photos to prove that, taken as I was opening the package.

I was surprised to find a power adapter included!

The clock's electronics are distributed onto three PCBs, shown in the photo below:

• the power board (on the left), containing the 5V regulator and the high voltage switching-mode power supply; this board is SMD-only and all parts are pre-soldered;
• the control board (on the right), which contains the microcontroller and the Nixie driver; this board is mainly through hole, the sole SMD component (pre-soldered) being the RTC (DS3231);
• the display board (middle of the photo), designed to fit IN12 Russian Nixie tubes; this board also has some SMD parts pre-soldered (LEDs, connectors etc).

Remarkable and original is the fact that two of the PCBs are actually part of the enclosure: the power board is the back panel, the display board being the front panel. For the back panel, this is pulled off by using only SMDs, with no traces or pads on the outside part of the board. Did I mention that the power board comes with all (SMD) parts already soldered?

The inclusion of the boards as part of the case is a novel approach, worth applying to future projects, with obvious advantages (reduces the number of fasteners/screws/standoffs, eliminates the attachments between the PCBs and the front/end panels etc).


I assembled the clock following the detailed instructions provided. Most of the required soldering is on the control board. Some attention must also be paid to positioning of the Nixie tubes on the display board before soldering them. After about an hour of work I had the Akafugu Nixie clock up and running. The result is shown in the photos below.

Beside being a cool geeky gadget, Akafugu Nixie clock can also be used as a functional alarm clock. The clock's functions are set by using the rotary encoder. Each tube can be lit up by an RGB LED (placed right under). The software, Arduino-compatible, is open source and can be modified using the Arduino IDE, then uploaded through the 6-pin FTDI interface/connector.

An improvement I would do is to allow for the easy replacement of the Nixie tubes, in case one gets burnt out (as it could happen with tubes, in general). This can be achieved by soldering tube socket pins on the display board instead of soldering the tubes directly to the board. I am sure Akafugu thought of this already, but they may have opted against it because it makes the Nixies stick out a bit more. I was actually going to follow up myself with this improvement, but the socket pins I found are too thick (~2mm) to go through the 1.5mm holes.


Overall, I was impressed with how nicely designed and well engineered this clock is. As a kit maker myself, I can appreciate the amount of work that went into creating this kit, from designing the hardware, to choosing the components, to cramming them all in such a compact space, to writing the software. Kudos for making it so easy to assemble, even by a beginner, with spectacular results.


For someone who likes Nixie clocks, the Akafugu Nixie clock is definitely a must-have.
Those who like clocks should add the Akafugu Nixie clock to their collection.
Those who like electronic kits will find the Akafugu Nixie clock kit inspirational.

User-friendly configuration of a Wi-Fi device

My previous post enumerated a few methods for configuring a device to connect to the home Wi-Fi network.
One of the friendliest way was number 4 (Creating a temporary ad-hoc Wi-Fi network). This method was chosen by Twine and also by HeatMeter and Belkin WeMo.

In normal use, the device connects to the home Wi-Fi network as a client, then sends (http GET/POST) the collected data to a web server.

Sometimes, when the device needs to be configured, it creates its own Wi-Fi network and runs a local web server. At this moment it allows other Wi-Fi devices (PC, smart phone etc) to connect, as clients, to the local web server and send configuration data, specifically the name of the home Wi-Fi network and the password. Once this configuration data is acquired and stored internally (in eeprom), the device returns to its normal state and uses it to connect to the home Wi-Fi network.
The configuration mode is selected by the user. One simple method is by holding down a button after a reset. Another is by placing the device (which has on-board accelerometer or even a tilt sensor) in a specific orientation (as done by Twine).

Below are diagrams I drew to show these two modes of operation (configuration mode and regular use mode).

The steps are:
1.After reset, if a switch is pressed by the user, the board enters the configuration mode. This makes  the Wi-Fi module a Wi-Fi server.

2.The user connects to it from laptop. Then user is presented with a web page that contains a form allowing the selection of the Wi-Fi networks that were detected, and the password.

3.These 2 elements (network name and password) are then saved in the eeprom. They will be used later to access the Wi-Fi network any time the sensor data gets sent to the collection web server.

Steps:
1.Data is read from the sensor.

2.Sensor data is sent as an http POST request through the Wi-Fi module.

3.Wi-Fi module posts the sensor data to the web server.

A nice feature for a network-connected device is that it can get program upgrades remotely, "over the air" in the case of Wi-Fi. This requires a bootloader that can connect to the internet and checks if a new version of the program is available for download on a given web server. The Readiymate team wrote such a bootloader for ATmega1280/2560 (the processor(s) found on Arduino Mega).

The next diagram shows how the remote program upgrade would work.

The steps are:
1.Bootloader makes an http GET request through the Wi-Fi module.

2.Wi-Fi module passes the request the web server used for “program updates”.

3.Web server starts streaming the latest program file (sketch).

4.The sketch is uploaded into the program memory.

User interaction when connecting WiFi devices to network

I spent some time recently analyzing methods for passing the WiFi parameters (network name and password) to a device, in user-friendly manner and on the cheap (that is, by using minimum extra hardware).

This challenge (of selecting the WiFi and entering the network password) was already solved in many different ways, from using the remote control to select characters displayed on the TV screen (as done by Apple TV, XBox etc), to creating an ad-hoc WiFi network (as done by WiFi thermostats, Twine and others).

The bottom line is that every WiFi device must somehow present the users with an interface that allows them to type in the network password. How this is solved determines the user-friendliness of the device and influences the final cost of the product as well.

Here are the methods I found so far. I am sure this list will be extended and improved with details, hopefully also based on the readers' comments and feedback.

1. SD card that includes a text file with network name and password
The user edits the text file on any computer. The SD card is then transferred onto the device. After the device is powered, the settings are stored internally and the SD card can be permanently removed. 
Pros:
- user-friendly and almost fool-proof;
- easy to implement in software;
- SD card may be also used for storing other data (backup in case of network disconnect, power outage etc);
Cons:
- need access to a PC (any text editor would work);
- adds about $6 to the total cost of the device (SD socket, SD card);
- device may need to be shipped with a an SD card USB adapter (adds another $2).

2. Bluetooth – The user interface is provided by a smart phones that communicates with the device through Bluetooth.
Pros:
- very user-friendly user interface through the smart phone app (e.g. Android), that uses a full keyboard and a complete feedback (similar to text editor);
- easy to develop the software for Bluetooth communication for the device;
Cons:
- adds $5 to the cost of the device (BT module);
- a simple application (e.g. BlueTerminal) needs to be downloaded by the user on the smart phone;
- may not work with iPhone, which requires Apple-licensed BT modules.

3. Using QR code that ships with the device - patented, licence-able technology; to investigate further (price, complexity etc.);

Pros:
- (maybe) user friendly, with minimal user interaction: smart phone app leads to a web site that requires the user to input the password;
Cons:
- pay royalties;
- need smart phone with camera and software app for QR codes.

4. Creating a temporary ad-hoc Wifi network (as used by some smart WiFi enabled thermostats)
Pros:
- easy to use web interface;
Cons:
- need a computer that can connect to the existing WiFi;
- requires development of the web site (for inputting the password);
- requires a way to switch the device between the setup mode and regular operation (when already connected to the WiFi). (Note: The above mentioned Twine uses an accelerometer chip for this purpose.)

5. Include an LCD screen with touch sensor or buttons (as in Nest).

Pros:
- all inclusive solution, no other equipment required to interface with the user;
Cons:
- adds to the final cost (at least $4);
- may be cumbersome to use, since the display is quite limited in space;
- makes the device bigger;
- software to handle the user interaction can be quite complicated (for such a simple task);
- waste of resources, since the LCD screen and buttons/touch may be used only for this purpose (user input).

6. Use a wired (custom, non-PC) input terminal, with screen and keyboard, that communicates on serial (RS232, RS485, TTL) interface with the device.

Pros:
- simpler software (processing the commands received on the serial interface);
- does not require extra hardware on the device itself;
Cons:
- need to provide the terminal hardware as well (OK solution when the device installation is done by a trained person).

7. Use an infrared (TV, VCR, stereo etc) remote control
Pros:
- ubiquitous, everybody is guaranteed to have one around;
- software is relatively easy to develop;
Cons:
- user interface not friendly; it would require some user feedback (display);

8. NFC (Near Field Communication) - to be researched
Pros:
- friendly user interface through the smart phone;
Cons:
- requires a smart phone;
- need to develop app for smart phone.



9. Direct connection to PC through USB/FTDI cable - as done by the readiymate board
Pros:
- the simplest to implement method: the board's microcontroller listens to and interprets the serial commands from PC;
- change the network name and password through either the serial monitor (command mode style) or through a GUI app that translates button clicks into serial commands;
Cons:
- requires on board FTDI chip (adds about $5 to the board's cost);
- requires development of the PC (GUI) app that talks to the board;
- also requires the user to download and install the app on the PC.

Raspberry Pi AlaMode

The great team of Wyolum announced that their Raspberry Pi AlaMode is available for pre-order.
This board, shown in the photo below, is Wyolum's answer to interfacing any number of hardware shields, sensors and servos to the Raspberry Pi.


AlaMode is an Arduino compatible board that plugs right on top of the Raspberry Pi computer. It also gives you:

• extremely accurate real time clock DS3231 with backup battery
• micro SD slot
• direct headers for plugging in servos
• safe voltage translation between the Raspberry Pi and Arduino.

Stock ticker with Wise Clock 4 and WiFly

I should have titled this "Adventures in WiFly land - Part 2", a continuation of this post, but really there was no adventure. Things worked smoothly from the start. The main "challenge" was parsing the http response on the fly, since the (truncated) response string itself is about 1500 bytes (3/4 of the RAM in a 328), which is the size of WiFly's receiving buffer.



The code (download from here) performs these steps:

• send http request to yahoo site, specifying the stock symbol;
• read the http response and find the token that identifies the stock price, in this case "last:";
• read the next few characters that represent the stock price;
• display the symbol and the price on the 3216 display.

This crude version is based on the WiFly_WebClient sample code from sparkfun. For display, it uses the HT1632 (header and c) files that are part of Wise Clock 4 library (but also supplied in the zip file). The software should work with any Arduino connected to a serial WiFly and a 3216 display from Sure Electronics.

The plan is to integrate this code as a new application in the Wise Clock 4 software. Stock symbols should be user-configurable and read from the SD card (as opposed to being hardcoded as they are now).
Also, the direction of the stock move, read from the http response as well (after the token "change"), could be shown in red for "down" and in green for "up".