The Mysterious CFexpress Card Specification / Pinout

It seems like CFexpress is going to replace CFast and CF card as the new de-facto DSLR storage medium, at least for Japanese camera manufacturers. The Internet kept its mouth very shut about what this CFexpress Card actually is, with specification no where to be found. However, piecing a few separate pieces of information together,… Continue reading The Mysterious CFexpress Card Specification / Pinout

sparsebundle-fuse: Another Implementation for Reading / Writing MacOS Sparsebundles on Linux

There are already a sparsebundle implementation for Linux, but that’s read-only and only supports FUSE. This implementation is read / write, AND supports NBD (network block device) so the sparsebundle actually appears as a block device on the system, without you needing to loop mount the file in FUSE. There are some useful things that… Continue reading sparsebundle-fuse: Another Implementation for Reading / Writing MacOS Sparsebundles on Linux

DIY $10 Slack Notification Light

[youtube https://www.youtube.com/watch?v=BT3PeNsmyPA&w=560&h=315] While being isolated at home, my company uses Slack more heavily than ever, and that Slack chime is starting to get old. What if there’s a physical light that can notify me instead? I have a Smoko ambient light and a few of Digisparks lying around screaming “use me!”. So I started the… Continue reading DIY $10 Slack Notification Light

The Making of the Library Occupancy Estimation System, Part 5 – the Enclosure

It’s almost time to deploy the ESP8266s. I switched from the previous board to wemos mini lite, a smaller board with a variant of ESP8266 (ESP8285). The ESP8285 includes a on-chip 1M EEPROM, reducing the cost. The most important difference is that the newer boards don’t have pre-soldered pin headers. Desoldering pins from the previous… Continue reading The Making of the Library Occupancy Estimation System, Part 5 – the Enclosure

The Making of the Library Occupancy Estimation System, Part 4 – the Frontend

The only part missing was a front-end. It is 2017, and splitting up front-end and back-end is now a must. This is even more true in this project: serving html and other resources from my free Heroku server does not sound like a good plan – with only 1 web instance, the server can be… Continue reading The Making of the Library Occupancy Estimation System, Part 4 – the Frontend

The Making of the Library Occupancy Estimation System, Part 3 – the Server

So the sniffer part was complete. The server was the missing piece of the puzzle. The server needs to do several things Receive data from the sniffer and decrypt Save sniffed data (probe requests) to a database Analyze probe requests and deduce occupancy Provide public APIs for retrieval of occupancy information I’m using python3 for… Continue reading The Making of the Library Occupancy Estimation System, Part 3 – the Server