Tag Archives: hack

Adafruit Bluefruit LE Micro into Wowwee Robosapien

I bought an Arduino Micro for a project a little while ago, found it easy to develop with and wondered where else I could use one. There are two Robosapiens in our house, so one of them went under the knife for a brain transplant. I chose an Adafruit Bluefruit LE Micro this time, so I could disconnect the USB cable and control the Robosapien over Bluetooth.

The Robosapien’s getting on in years and resources explaining what’s inside it are disappearing from the WWW. Markcra’s Robosapien pages are an invaluable starting point, though I never did find a complete list of pinouts for the U2 controller IC. Here’s the list I used while adding the wire extensions for the prototyping board:

U2 pin Connected to
P10 IR
P11 Finger/toe/heel switches left
P12 Grip switch left
P13 Shoulder switch left
P14 Finger/toe/heel switches right
P15 Grip switch right
P16 Shoulder switch right
P17 Microphone
P20 LED
P21 LED
P22 LED
P23 LED
P24 LED
P25 LED
P26 LED
P27 LED
P30 Grip motor open left
P31 Grip motor close left
V01 Speaker
V02 ?
P32 Shoulder motor left
P33 Shoulder motor leftexpecting to be able to
P34 Grip motor open right
P35 Grip motor open right
P36 Shoulder motor right
P37 Shoulder motor right
P40 Waist left
P41 Waist right
P42 Leg motor left
P43 Leg motor left
P44 Leg motor right
P45 Leg motor right
P46 ?
P47 ?

“Left” and “right” are from the Robosapien’s point of view. With 31 lines of I/O before any enhancements might be considered, I had to add some extra I/O in the form of 2 MCP23S17 SPI I/O Expanders. The Bluefruit LE Micro uses SPI to communicate with its Bluetooth module, so adding the MCP23S17s was straightforward. I failed to get a single CS (Chip Select) line to work with HAEN (Hardware Address ENable) set on the MCP23S17s, but one CS pin on the master per MCP23S17 works a treat.

Prototyping board close up

Prototyping board close up

The Arduino code is very simple – it reads a character from either the USB serial port or the Bluetooth UART into a command buffer. ‘Commands’ on the modified Robosapien are trivial – motors and LEDs can be turned on and off,¬† delays of 0-999ms can be inserted and triggers for low/high on the switches can be waited for. For example, “s+” is “left shoulder up”, “S-” (lower/upper case for left/right!) is “right shoulder down”, “w0” is “waist motor off”. “L=” is right leg motor ‘brake’ (high signal to both sides of motor driver, though the brake effect is very weak). “e000” is all LEDs on. “e255” is all LEDs off. There are 8 LEDs. “W500” inserts a delay of 500ms before the next command is executed. “tb1” is “trigger when left button signal is high”. “q” turns off all motors.

Behaviour Send text string
Funky walk w+W300s+S-l-L+w-W360s-S+l+L-w+W360s+S-l-L+w-W360s-S+l+L-w+W360s+S-l-L+w-W360s-S+l+L-w+W360s+S-l-L+w-W360s-S+l+L-w+W360s+S-l-L+w-W360s-S+l+L-w+W360s+S-l-L+w-W360s-S+l+L-w+W360l0L0s0S0W500q
Turn in place w+l+L-W075l-L+W075w-W075l+L-W150l-L+W075w+W075l+L-W150l-L+W075w-W075l+L-W150l-L+W075w+W075l+L-W150l-L+W075w-W075l+L-W150l-L+W075w+W075l+L-W150l-L+W075w-W075l+L-W150l-L+W075w+W075l+L-W150l-L+W075q
‘High’ kick w+h+H-s+S+W999W600qS-tS1S=l-W999W150L+W150L-W150L+W150L-W150L+W150L-W150L+W150L-W150L+W150q

Source code for Arduino IDE is here: robosapienarduino.tar.gz

While the brain transplant is a success, losing the behavioural repertoire and vocalisations means there’s plenty still to do to return the Robosapien to full health. It being an old (nearly ten years?) toy, I’m wary of physically modding it further – such as adding contact sensors to its feet – and using it more in case I break its mechanisms.

The Robosapien has lived up to its claims of “made to be hackable”, but PCB-hacking is fraught with dangers. I’d like to see “made-to-hack” toys have their toy-behaviour controllers on pluggable daughter boards, exposing well-documented headers for owners who want to try their hand at brain surgery.

Having successfully operated on one patient, I’m looking forward to using the Adafruit Bluefruit LE Micro on new candidates… and there’s an unloved, apparently-hard-of-hearing Zoomer in the toy cupboard downstairs. “Zoomer! Here boy! Whassis? Screwdriver! Roll over!”

Add a search engine to Ubuntu Touch browser

You can’t add search engines with the browser GUI, perhaps because Ubuntu Touch is a Work-In-Progress and it’s still early days. Adding search engines to browsers still has patchy support from major browsers, even though the OpenSearch standard is donkey’s years old. I installed Ubuntu Touch on my Nexus 4 after experiencing the “Sleep Of Death” too many times and wanted to use my Firtl search proxy in Touch’s browser.

I located the configuration files (they’re OpenSearch XML description documents, which is handy!) by using grep -r to search for one of the existing search engine names. The search engine description documents are located (on my phone) in

/usr/share/webbrowser-app/webbrowser/searchengines

The / filesystem appears to be mounted read-only and must be remounted read-write to make changes. I did this with the command

mount -o remount,rw /

Copy your search engine’s OpenSearch description document into this directory and next time you attempt to set Ubuntu Touch’s web browser’s search engine, you should see the new search engine in the list. Don’t forget to remount / read-only.

Happy Searching!

Brother PT-1230PC on Ubuntu Linux

I found one of these in LIDL recently at the kind of price that usually makes me buy gadgets out of curiosity. My wife had been talking about writing out price labels for a stall in our local market for products she has in her web shop. I wondered if this little label printer might make the job easier.

Brother PT-1230PC label printer

Brother supplies no non-Windows drivers for this product. A quick search reveals a neat Glade/Perl application called blabel by Ari Sovij√§rvi that formats two-line labels for the PT-1230PC. I needed to print about 140 price labels, so the several cm feed that seems to be a part of every ‘job’ on this little printer would have wasted some pretty pricey label tape.

Without knowing anything about how the printer is controlled, it seems the best way to avoid the inter-label feeds is to combine several labels into one image and print that aggregate image as a single job. I created a CSV file using phpMyAdmin on the web shop which held the product name and price in two columns. A shell script using ImageMagick converted each line into a single label 120×64 pixels and appended it to an 11-label image, which is then printed as a single job using a ‘–fromfile’ command line argument I added to blabel.

Single 120x64 pixel price label

Single price label

I didn’t do too much trial-and-error on the expensive label tape but the largest image I printed was 1320×64 pixels for 11 labels. I chose 11 because the CSV file had a number of rows divisible by 11. Each label is 120 pixels wide. 20 labels caused the printer’s LED to flash (an error?), so the maximum image is somewhere between 1320 and 2400 pixels wide.

11 labels combined with ImageMagick's convert +append

11 labels with ImageMagick’s convert +append

The original deb from Ari’s site is below, along with a patch that adds the –fromfile command line argument. The image you print must be black and white PNG 64 pixels high. I use it like this:

blabel --fromfile=biglabel.png

blabel with –fromfile patch in zip archive

I’ve never edited Perl before (or code with so many ‘ghetto’ comments =p) so, you know, caveat emptor.