Like so many other home appliances, it’s likely that even your air conditioner has a serial interface buried inside it. If you’re wondering why, it’s because virtually every microcontroller on the planet has a UART built in, and it’s highly useful for debugging during the development process, so it makes sense to use it. Thus, it was only a matter of time before we saw a hacked airconditioner controlled by a Raspberry Pi.
[Hadley] was growing frustrated with the IR remote for his Mitsubishi air conditioner; it can issue commands, but it’s a one way interface – there’s no feedback on current status or whether commands are received, other then the occasional beep or two. Deciding there had to be a better way, [Hadley] grabbed a Saleae Logic Analyser and started probing around, determining that the unit spoke 5 V TTL at 2400 bps with even parity. The next step was to start talking back.
Continue reading “Air Conditioner Speaks Serial, Just Like Everything Else”
The members of Shackspace got their hands on an antiquated robot arm. It’s a Mitsubishi Movemaster RM-101 and was probably manufactured in the mid 1980’s. There’s almost nothing out there that tells you how to use the thing, and so they set out to figure out how to control the hardware.
This is a great example of how an EPROM dump can be really useful. After further inspection the team discovered that the arm is driven by a Z80 processor whose program is stored on an EPROM. The first thing the guys did was dump the memory since the aging storage will be useless if just a few bits become degraded. This dump will be really useful for others whose chip has already given up the ghost. The data from that dump was disassembled and painstakingly pawed through to figure out what commands were being sent to the arm. This technique worked, as the team was able to re-implement the control protocol and has already used the arm for some light painting and pen plotting (seen above). After the break you can see a control demonstration.
Continue reading “Salvaged robot arm used for light painting and pen plotting”
It’s a few years old, but [Brian360’s] method of unlocking the hard drive on his Mitsubishi Multi-Communication System is quite interesting. Mitsubishi describes their MMCS as a human-vehicle communication tool. It’s basically an in-dash screen and controls to display navigation maps and play music. [Brian] found that the hard drive for the MMCS in his 2008 Lancer was locked, and could not be cloned and swapped out for a larger drive. Sound familiar to anyone? Hard drive locking has been used in many systems, including the original Xbox, which we’ll get back to in a minute.
The setup seen above was used to grab the hard drive password from the system itself. A custom adapter card was built and plugged in between the hard drive and the MMCS hardware, with test points for each of the data line. [Brian] attached a digital storage oscilloscope, and after a bit of poking around, found a way to trigger the scope when the password was requested. He explains the process of converting the captured data into an ASCII string password.
With that in hand how would you unlock the drive? The favorite tool for this is hdparm, a tool which was used with early Xbox unlocking but which is still in use with other hardware today. Now brian has a disk image backup and the ability to swap out for larger hardware.
The fine folks at Mitsubishi Electric Research Labs (MERL) are demoing a new touchscreen system that may make small devices easier to use. An extension of their LucidTouch technology, NanoTouch has a small screen on the front and a touchpad on the back. Their test unit features a 2.4inch screen. The screen displays where the user’s finger is on the back touchpad as if the display was transparent. The user’s finger no longer obscures the screen surface, so it’s much easier to hit small buttons. In testing, researchers showed that targets just 1.8mm across were easy to hit. That’s much smaller than the iPhone’s touchscreen keyboard. Here’s a video demonstrating the new device.