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Sigfox Base Station Reverse Engineering - Part 4: SDR
Finally I’ve come to the most complex part of the Sigfox (ignoring the standard PC motherboard) - the SDR (Software Defined Radio). I had originally intended to only get a high-level block diagram of this part, but I ended up going a lot deeper than I planned, and have a...
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Writing BDM Interface for the Glasgow Interface Explorer
As I’ve been working on reverse-engineering the SDR module from the Sigfox base station, I also wanted to dump any ROMs from the device. The audio interface chip was easy, since it had an external SPI flash that could be dumped with flashrom or another tool. The microcontroller on the...
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Sigfox Base Station Reverse Engineering - Part 3: Low Noise Amplifier
Before moving on to the more complex SDR module, I decided to take a look at the external LNA (low noise amplifier) first. This has some similarities to the power amplifier I covered in the previous post, except that this amplifies received signals and lives near the antenna, rather than...
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Sigfox Base Station Reverse Engineering - Part 2: RF Power Amplifier
Now that I’ve given an overview of the Sigfox base station, I’ll start diving deeper into the individual components. I’ll start here with the RF Power Amplifier, denoted as BPA (Base station Power Amplifier, perhaps? But it’s also possible it could include French words as that is where Sigfox is...
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Sigfox Base Station Reverse Engineering - Part 1: Overview
Over a year ago I obtained a Sigfox base station, or TAP (Transfox Access Point), from a company that was moving and wanted to get rid of some of their old equipment. Sigfox operates a LPWAN (Low-Power Wide-Area Network), more-or-less as a competitor to LTE Cat. M/NB-IoT or LoRaWAN. I...
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Tektronix TLA Logic Probe Leadset Replacement
GitHub repo containing the PCBs and 3D models in this post: https://github.com/farlepet/tek-tla-probes A while back I got a Tektronix TLA5202 logic analyzer, as I wanted a standalone unit I could use without needing to fiddle around with connecting a USB logic analyzer to a computer/laptop and dealing with the occasional...
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Using Linux device-tree with PCIe devices
Back in 2015, Linux deprecated the /sys/class/gpio interface in favor of using other methods to access GPIO pins. It’s been over 8 years since then, and the interface is still around, and thus some systems still make use of it. Many of these are fairly easy to change to use...
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Keithley 615 Electrometer Interface - Part 1: Replacement PCBs
This is a project that I started a bit over a year ago, though which is still in progress at the time of writing. There are two GitHub repos associated with it: PCB designs: https://github.com/farlepet/keithley-615-printer-boards Firmware: https://github.com/farlepet/keithley-615-net-fw Background Several years ago, I came across a Keithley 615 electrometer that was...
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Welcome!
Welcome to my blog! I mainly plan on using this blog to write about projects that I work on. I may also write about reverse-engineering efforts, or whatever else I may find interesting.