Jacob

Docker Builders for Easy Updates

One of the most frustrating things for me is when a new version of a software is released with a fix, feature, or otherwise useful addition I’d like to use, but the package maintainers for my Linux distro haven’t caught up yet. Some of the packages are so far behind it’s silly. I recently decided that for software I use regularly, and is updated regularly, I was going to start using a Docker container to build it and keep my…

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Why the Alinco DR-735T can’t transmit at 9600bps

The Alinco DR-735T is a very capable, dual band, dual VFO, full duplex, cross-band repeat capable radio, with an industry standard mini DIN TNC connector on the back for working packet. While I was reading about the capabilities of this radio in its manual, I noticed that it can received 9600bps packet radio, but can only transmit up to 4800bps. The reason why was not intuitively obvious to me upon first glance at the radio’s specifications, so I went deeper…

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J-Pole Antennas for Ham Radio

If you’ve read any of my other posts, you know I love to build, tinker, and hack at stuff. Antenna-building is something I’ve not made a foray into, until recently. I have a dual-band handheld radio for the 2m and 70cm bands. The so-called rubber-duck antenna that comes with it performs ok but it isn’t ideal. I could get into my local repeaters which are about 10mi away with enough power to break the squelch, but my audio was weak…

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Take notes using Joplin

The hunt for a self-hosted notes system To be honest, I love self-hosting tools. I think it has to do with my love of learning, but I digress. I know there are gobs of note-taking/sharing/synchronizing apps out there, many of them free, but they all lacked features, and I wanted to self-host. What I Was Looking For I wanted a note-taking app, with the following capabilities: Self-hosted Synchronization across devices E2EE (end-to-end encryption) Rich media note-taking ability Markdown style note-taking…

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Who knew installing Windows could be so hard?

Recently, I upgraded my wife’s 2-in-1 laptop to an SSD from a 5400RPM platter drive. The hardware installation, which is usually the tricky part on laptops, ended up being the easiest part. Installing Windows 10 ended up taking me down a road for a couple of hours filled with frustration and irritation with not only Microsoft, but ASUSTek too! Here’s my experience. The Problem The standard installation procedure for Windows via USB for a good while has been to dd…

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Calculus Made Simple

To many, integral and differential calculus may as well be a foreign language from an alien planet. Many people don’t grasp the fundamental concepts which drive the calculus, and consequently fail to derive the value they otherwise could from that knowledge. I’ve always found the key to making use of some bit of knowledge is to internalize it, to restate the concepts in terms that are familiar and comfortable to you, but to compare this restatement and internalization to the…

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Kernel Design: Microkernel vs. Monolithic

Motivation This hotly debated topic has been around for decades, and it is just as alive today as it was 28 years ago. The truth is, there are fundamental differences in the theory which drives the design of a monolithic kernel versus a microkernel. In this post, I will extrapolate from my knowledge of various kernel designs to explore what these two primary types are, what their features, benefits, drawbacks and implications may be. I’ll also briefly explore the extension…

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Virtualization for Embedded Systems Series: Type-2 Hypervisors Deep Dive

In the previous post in this series, we dove deep into container technology and looked at how to implement some functionality into containers applicable to embedded devices. In this post, we will look at type-2 hypervisors and dive deep into practical ways to use them for embedded systems. This post will be light on content as I am quite busy currently, but wanted to wrap up this series. I will try to circle back and dive deeper into this topic…

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Better JTAG on the Cheap with the FT232H

A couple of weeks ago I wrote a post about using the FTDI FT232R as a cheap JTAG debugger. I’ve been using it for a bit now to play with my Raspberry Pi 3B, and now that my code size has grown, the FT232R is just too slow to cut it. Here’s a breakdown: on the FT232R, the max speed I can set the adapter to is 3MHz. This has given me a transfer speed (loading via GDB) of around…

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Raspberry Pi

JTAG On the Cheap with the FTDI FT232R

JTAG 101 What is it? JTAG stands for the Joint Test Action Group, and the TAP or Test Access Port this group defined is one of the most (if not the most) common way to program and debug embedded devices and computers of all flavors. For the professional, JTAG devices are bountiful and usually not too much of a strain on the commercial budget. But for the hobbyist, things aren’t so peachy. A Segger J-Link EDU can be had for…

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