Acu-Link Bridge and Acu-Rite Weather Station Teardown

I got an Acu-Rite Weather Station as a gift and, of course, I cracked open some of the parts to see what was inside.

I didn’t open up the 5-in-1 sensor unit which sits outdoors and measures wind speed & direction, temperature, humidity and precipitation. I did crack open the 01500RX display console, and the Acu-Link bridge which receives the sensor data over a wireless link and relays it to the Acu-Link webservice via an ethernet connection.

The 01500RX had a number of blob-top chips-on-board. I didn’t try to figure out what they were. I was most interested in the wireless receiver that picks up sensor data.


The receiver was on its own PCB.  The chip is labeled MICRF211AYQS 1226, which seems to be a 433MHz RF receiver from Micrel with a demodulated signal output.

In the internet bridge, I found the same receiver, along with a low cost ethernet enabled microcontroller, and a surprise.

Acu-Link Bridge PCB


The microcontroller is a PIC18F67J60, very bare-bones 8-bit chip with an ethernet port, 128K of flash, less than 4K of RAM, and 8K RAM for the ethernet buffer. This is apparently enough to run a TCP/IP stack with a bare-bones web server, but it doesn’t exactly leave a lot of room for adding additional functionality, like the ability to make sensor data available locally via HTTP.

I also mentioned that there was a surprise. You can see it too, in the lower left of the photo, a third PCB, this one, apparently holding a serial to RF transmitter. I don’t know what it is for. Acu-Rite doesn’t talk about it at all in any of the marketing materials or users manual. My guess is that it might work as a repeater for the sensor data, that, or they’ll have some actuator equipment in the future, like, say, something that could toggle the mode on an automatic irrigation system based on local weather conditions.

Anyway, that’s what I found. I thought it might help out other people who are intrigued by Acu-Rite’s offerings and interested in hacking them for their own purposes.

The Sorry State of Thunderbolt Peripherals

In theory, Thunderbolt is awesome, one tiny port that can be used to connect monitors, GPUs, high speed storage and other peripherals to laptops and desktop computers.  What’s not to like?

Unfortunately, Thunderbolt peripherals are slow to arrive on the scene.  Apple released their first computers with Thunderbolt ports over a year ago. To compliment them, they released the gorgeous and expensive Thunderbolt display.

Don’t get me wrong, the Apple Thunderbolt display is a perfect demonstration of why Thunderbolt is so cool. The display has one cable with two connectors, a magsafe connector to power an Apple laptop, and a Thunderbolt connector.  The display itself is gorgeous, includes speakers and a webcam, and it expands that single Thunderbolt connection into gigabit ethernet, three USB2 ports, a FireWire 800 port, and another Thunderbolt port that you can use to attach another Thunderbolt display, or a mini-DisplayPort adapter. Awesome!


On the other hand, it is $999. That is by no means a bad price for a great 27″ high resolution display, but I’m happy with the 24″ display I already have and in no hurry to replace it. But then there is mess. Ugh! I’d love to reduce that mess down to a power cable and a Thunderbolt cable.

In theory, I should be able to buy a docking station. In practice only Belkin and Matrox have even announced Thunderbolt docking stations, but neither of them are shipping, and when they do, they are expected to run $250 – $500.

Apple had a one-year exclusive on offering Thunderbolt ports on their computers. Now that that has ended, I hope we’ll see more competition, but it may take a while. NewEgg only has ~5 motherboards with Thunderbolt ports right now. A bigger issue though may be that so far, Intel is keeping a tight reign on the chips required to interface with Thunderbolt.

I’d be quite happy with a simple device that connected to a Thunderbolt port and provided USB3 ports and DisplayPort connection. I could hang USB ethernet and audio adapters off of that.



There are so many interesting options for hackable ARM devices, I don’t really know where to start, so I’ll start with the ODROID-X.

The ODROID-X is a development board based on the Samsung Exynos4412 quad core ARM Cortex-A9 SoC with a Mali-400 quad-core GPU. The board adds 1GB of RAM along with 6 USB 2 ports, a 10/100 ethernet port, micro HDMI and analog audio audio in and out. It sells for $129.

This makes it one of the faster options available, but also one of the more expensive when compared to many of the Chinese options. It also has the advantage of already supporting a full Linux distro (ubuntu), whereas many of the cheaper options currently only have support for Android.

A brief history of hackable ARM devices

Once upon a time, there was the SheevaPlug, a $99 computer with a 1.2GHz ARM CPU, 512mb RAM, 512mb of flash storage, USB2 and an SDHC card reader that ran Linux. The SheevaPlug gave birth to inexpensive commercial products, like the PogoPlug, and it’s cousin, the heavily discounted Seagate Dockstar.

Since then, there has been an explosion of ARM-based development platforms. The SheevaPlug was based on the Kirkwood system-on-a-chip from Marvel, who partnered with GlobalScale Technologies to create development and reference designs that could easily be customized for various applications. Similarly, Texas Instruments, which has its own ARM based SOC families, created the Pandaboard, BeagleBoard and BeagleBone to encourage people to develop applications for their chips. Globalscale and Marvel haven’t rested on their laurels, either, they’ve created a number of additional variants on Sheeva platform, some with video output, others with SATA interfaces, additional GigE, WiFi, and other differentiators.

This is really just scratching the surface. Samsung, Qualcomm, Nvidia and Broadcom all make their own ARM SOCs, and there is an explosion of devices based on Chinese chips, like the Allwinner A10 (single core ARM Cortex A8 + dual Core Mali GPU), Rockchip 3066 (dua core ARM Cortex A9 + quad core Mali GPU) and AMLogic 8726-M3.