40% Failure Rate of Sumnacon Banana Plug Test Leads
2 of 5 silicone banana plug test leads I bought off Amazon were duds right out of the box, failing to pass a simple continuity test.
SSL Fixed, Now Hosted on Digital Ocean
I finally fixed my SSL, so this blog is now back online! I’ve migrated my hosting from an Amazon Web Service EC2 instance to a DigitalOcean droplet.
feyerchak.net SSL Certificate Expiration
I’m having problems renewing the feyerchak.net server’s SSL certificate, which will expire on 31 October 2017.
Line Following Robot – Building a 3.3v Power Module
The Pololu m3pi robot has an “mbed” socket for an optional compute module and an “XBee” socket for an optional communications module. Unfortunately, the communications module is expected to source its power from the compute module (docs). I’ve built my own power module to support a communications module in the absence of a compute module.
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Secure Disposal of IDE Hard Drive
I was asked to securely dispose of an old 3.5″ IDE hard drive. I wiped its data, then scattered its physical components across multiple waste disposal streams. The technique I present here is broadly applicable and does not depend upon the OS installed on the target hard drive or the OS installed on the lab machine.
Wireless Serial Loopback with Bluetooth and USB Power on Linux
I’ve powered the Wireless Serial Loopback with Bluetooth on Linux exercise via the TTL-232R-3V3 USB cable by introducing a voltage regulator component. This eliminates the bulky and expensive bench power supply.
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Wireless Serial Loopback with Bluetooth on Linux
I’ve successfully passed serial data in both directions over Bluetooth via a Bluetooth device mapped as a Linux serial port device. I used a Roving Networks RN42XV embedded Bluetooth module and a Linux host with a CSR V4.0 Bluetooth USB dongle. This builds upon my previous wired serial loopback exercise.
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Wired Serial Loopback on Linux
In preparation for some upcoming serial-over-Bluetooth work, I’m validating my understanding of how to loop back a serial connection in Linux using the “Minicom” serial terminal server software and two USB-serial adapter cables.
Line Following Robot – Flashing the 3pi’s ATmega328p Microcontroller
I successfully flashed a “*.hex” program binary onto my 3pi’s Atmel mega328p microcontroller using an Ubuntu 16.04 PC with the “avrdude” utility software and Pololu’s USB AVR Programmer V2.
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