Follow the bootable dos usb tutorial here.

Download the appropriate bios updater and unzip it on the flash drive you used.

Boot your machine. The bios update starts automatically.

Follow the boot/power instructions and enjoy your new bios.

It turns out that the trick is to search for ‘Cable Drag Chain’ and you’ll find the inexpensive pricing that we’ve all come to know and love on ebay. I picked up some 40″ 10mm x 15mm for about $12.

I updated my thermostat to one of these. It’s made by Homewerks (Home depot sells a filtrete branded version.) It’s not as cool as the NEST, but it’ll do the job of controlling a furnace/AC. The interesting part of this device is that the wifi interface can be cloud managed, making it possible to control the thermostat via my iPhone, iPad (or android) from anywhere with data connectivity.

It’s actually a fairly decent device for the money. It has a JSON api that allows you to get and set variables via web interface. There’s a fantastic PDF on the API that shows examples using curl (available on linux, mac, etc). What’s really interesting is that with a JSON interface, you could easily write your own application for mobile phones or just script up some commands from your choice of computing platform.

Wiring was interesting. On my ancient furnace (built by chrystler) I discovered some new details. The fan wire wasn’t connected at all! At some point, some A/C tech had installed a honeywell fan controller and the fan is activated by either the cooling or heating wires being engaged. (there is a manual switch inside the furnace. Argh!) However, I was able to re-use the fan wire as a C wire to deliver both sides of the 24v a/c transformer power to the thermostat. Wifi eats more power, and you need an external supply to feed that radio.

Setup is pretty neat. I loaded the radio thermostat App on my iPad, and once it discovered the thermostat, I had to join the ‘stats wifi network. Then I could configure my WPA2 network (excellent! Thanks for supporting proper protocols!) as well as a dynamic or static ip address. I opted for static the last time I configured it. –I reconfigured it a few times while I played around with wiring options.

The hardware in the device is rather interesting. It’s the first one I’ve seen with a wifi USNAP module. I’d expect to see more of these devices on the market. The price point is fairly low and the curl api is ideal. Hmm, arduino USNAP shield, anyone?

Resources:

Wiki (unknown owner) for developing: http://central.isaroach.com/wiki/index.php/Main_Page

PDF Documenting the Thermostat API. (local copy here) This is the interesting one.

This is his hand built version of a Stealth Electric Bike (Those start at $8k each!). Check out his build logs for this bike here and here. He even made the hub motor. The chassis is laser cut steel that he welded together and it’s powered by a custom pack of LifePo cells. Given the motor and voltage, this bike is capable of something like 50-60mph!

Be sure to check out part 2 which details the friggin liquid cooled motor, internal temperature monitoring and some huge phase wires for the brushless motor.

After I’d read this build – and was just amazed by it, I found out that Greyborg is actually a serious Ebike manufacturer who produces and sells motors, bikes and other parts. (Which explains the resources he could put into the build) I have to say that I definitely admire this guy. If he didn’t live on another continent I would take a road trip just to meet him and check out his creations!

I just gave it another test run and the car started perfectly. Now that the system has stayed working, I’m planning to develop the backend code a bit more. In addition, I have some more tricks up my sleeve…

I used an older Arduino simply because I wanted a quick and dirty 3.3v source for the iphone to arduino serial interface. The perfboard has a tip120 to drive the remote start, all the interface wiring for the car, power supply and the iphone interface. I tossed in a .01 cap at the power source just for extra filtering. The power supply is a switching charger from a broken iphone car charger. Efficient and free!

This is my quick build schematic. (Click to see the entire thing) The voltage divider on the left is so that the arduino can report the system voltage. it’s made of 3 10k resistors since I always have those on hand. The result is 1/3 of the 12-14v DC that the car has. From this, we can infer the state of the car: >13 is started. I plan to toss in a ds180 1 wire temp sensor later on as well. The pink highlighter was used as I wired things up.

Important: There’s an error in the schematic – I fixed it on my board but forgot to update it! The diode should connect on the other side of the resistor that connects the iphone serial RX and the Arduino 3.3v source. If you connect it this way, you won’t get any serial input on the iphone. It’s not lethal, just important!

(update 2: You can get the clean version of the schematic here: )

Requirements:

An old jailbroken iPhone, an Arduino, iphone breakout board (I used a PodBreakout Mini) 4x 10k resistors, 1x TIP120, a 5 volt switching supply cell charger (easier than building one), some wiring ability and a general understanding of unix/perl/arduino. (See the packages on my dev phone in this post.

The code:

You can get the code to make it all work here. (SMSresponder.pl, com.SMSresponder.startup.plist and

SMSresponder is a perl script that runs in a loop. Every 30 seconds it checks for a new message since the last time it ran. place it in /var/root/bin/ (you’ll need to create that directory) as this is where the startup system looks for it. You can put it somewhere else, just edit the plist to match.

Make it work all the time:

Copy com.SMSresponder.startup.plist to /System/Library/LaunchDaemons on the phone. This will start the script at boot.

The Arduino:

RemoteStartController.pde is a quick program that I wrote based on all sorts of other source I already had on hand. Notably, most of the code was adapted from Motokomp. I’ve added hooks for additional commands, but haven’t updated the iPhone perl script to do anything with the output.

How it works in real life:

I send a text message from my phone with the phrase: “Start 1234″ (1234 would be the password in the phone script). The phone gets the text then tells the arduino via serial interface to start. The arduino grounds the wire to the remote start that activates it. Meanwhile, the phone sends back a SMS saying ‘Executed’ to let me know that it got the message and is acting on it. In the future it’ll send back a message confirming that the start was executed as opposed to the I told him to do it method.

Project comments:

This thing works very well. I can probably get away with reducing the polling time on the iPhone, but I wanted to conserve resources. I spent two weeks testing the SMSresponder script running on the phone with perfect results every time. I still need to add some handshaking between the iphone and arduino, (iPhone: start dude. Arduino: OK!, iPhone: great let me sms that back to the man in charge.) Right now, the iphone sends the command and prays that the arduino got the message.

The remote start I’m using is an Avatal 3117 purchased via Amazon. (There are additional things added to make the subaru’s computer happy about missing the key) the main reason I bought this remote start is that it has an input wire for starting! When you ground it, the remote start will start the car. If you ground it again, the car will turn off. That’s how the arduino activates the remote start. In reality, there’s also a serial interface on most RS units today, but getting documentation on them seemed difficult. Besides, who wants to implement a new protocol just for a one-off build?

I’m seriously considering building a kit version of this hardware. It would include the iphone dock connector, programmed atmega, etc: it would tie all the prototype hardware into a single build – and maybe add a nice box and harness to make it work. (I used extra wiring bits from my remote start install to add a nice modular connector to the prototype)

Costs:

$20 phone – I got around $4 in line credit with the phone. Sometimes they include extra minutes in the deal making it even better.

Buy at least $10 for the pay as you go plan. SMS will cost $.10/each. Not the best, but nice for low investment. $10 gets you 100 messages.

However, if you find that you’re using the heck out of it, you can upgrade to a $15/month plan that gives you UNLIMITED TEXT.