Seeing the guts of devices is a fascination that many hackers share. [Txyz] tore down a 2nd gen Google Nest Hub for all of us to enjoy. The video after the break is well produced and relaxing to watch as various heat shields are removed and debug cables are soldered on.
The main SOC is an Amlogic S905D3G, a 4-core A55-based SoC. The important chips are meticulously documented, and it’s a fascinating look inside a device common in many people’s homes. One chip that’s of note is the BGT60TR13C, otherwise known as Project Soli. It is an 8x10mm chip that uses radar to detect movement with sub-millimeter accuracy. This allows the device to measure your sleep quality or recognize gestures. Luckily for us, [Txyz] has included a datasheet and a block diagram. First, the chip fills a FIFO with data samples. Once full, it will issue an interrupt to the main SoC, which empties the buffer via SPI.
The debug cables allowed him to capture traces of the SPI commands to the BGT60TR13C. [Txyz] focused on decoding the various data blocks and the configuration registers. Unfortunately, only a few registers are documented in the datasheet, and it isn’t apparent what they do.
If a hardware teardown isn’t enough for you, perhaps a software teardown to bypass Secure Boot might sate your interest.
Continue reading “Google Nest Hub Teardown”
The DSLogic open source logic analyzer is on its second release (the plus version) and [OpenTechLab] has a comprehensive review of the new model, which, unlike the original model, includes a different method of connecting probes and provides a separate ground for each input pin.
The device is pretty simple inside with an FPGA, a RAM, and a USB microcontroller. There’s also a configuration EEPROM and a switching power supply. The device stores up to 256 megabits internally and can sample 400 million samples per second on 4 of its 16 channels. [OpenTechLab] even puts the board under a microscope and maps out the input circuit.
Continue reading “DSLogic Plus Teardown And Review”
Logic analyzers historically have been the heavy artillery in an engineer’s arsenal. For many of us, the name invokes mental images of large HP and Tektronix iron with real CRT screens. Logic connections were made through pods, with hundreds of leads weaving their way back to the test equipment. The logic analyzer came out when all else failed, when even a four channel scope wasn’t enough to figure out your problems. Setting them up was a pain – if you were lucky, the analyzer had a PC keyboard interface. If not, you were stuck typing your signal names into the front panel keyboard. Once setup though, logic analyzers were great at finding bugs. You can see things you’d never see with another tool – like a data bus slowly settling out after the read or write strobe.
There have been a number of USB based logic analyzers introduced in recent years, but they didn’t really catch on until Saleae released their “Logic” line of devices. Low cost, high-speed, and easy to use – these devices were perfect. They also inspired an army of clone devices based upon the same Cypress Semiconductor parts. DSLogic designed by DreamSource Labs, can be thought of as an open source evolution of the original Saleae device.
DSLogic appeared in 2013 as a Kickstarter campaign for an open source logic analyzer with an optional oscilloscope extension. I think it’s safe to say that they did well, raising $111,497 USD, more than 10 times their initial goal of $10,000 USD. These days both the DSLogic and the oscilloscope extension are available at The Hackaday Store. In this review we’re focusing on the logic analyzer portion of the tool.
Click past the break for the full story!
Continue reading “Review: DSLogic Logic Analyzer”