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Quorten Blog 1

First blog for all Quorten's blog-like writings

Operating a complex home network… one of the ultimate ways of geekery. I personally have been operating a home network for some time, and I have to say… if the home network is built just for you and yourself, well that’s easy. But the moment you consider using a build-out geek home network that is operating and providing a service to others, well… sometimes that raises more questions than it answers.

First of all, you have to answer to the question of the users’ willingness, or more commonly the case, lack thereof willingness to learn about how the complex network functions. It’s funny, when you think about this. This is so baseline, so fundamental of an idea, yet it’s something that many engineers blissfully overlook. The fact that you can build fancy technologies that do nice things, that people will want to use them, but they will be utmost reluctant to learn about them? How did we fail to anticipate that this would happen?

Specificaly, in the case of computer networking at home, we have a very obvious precedent in the sector: utilities. Internet has often been called “the new utility,” and telecommunications is the name of the larger game. Why do we call them utilities? Because the users have a highly utilitarian attitude toward them! “Does it have a utility?” What benefit does it provide to me? Okay, fine, can I just reap the benefits and forget about the details of it?

Read on →

Sequential logic in Verilog, at the outset, is a little bit tricky because you must be careful to use the non-blocking assignment operator <= instead of the blocking assignment operator =, otherwise you’ll get incorrect simulation results. Okay, so now you’ve written up some sequential logic in Verilog and you get around to simulating it. “Wait a minute,” you’re wondering. “Sequential logic models the process of reading and writing to latch registers. This means when I perform an action on the risng edge of the clock, the results of it won’t be visible until the next rising edge of the clock, right?” Well, not quite.

Take, for example, the following simple Verilog code to implement a shift register.

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FPGA development has long been much more difficult than microcontroller and GAL development due to the lack of open-source tooling. In recent years, some open-source programming tools have been developed for Lattice. So, how are the supported platforms going today? Very much it’s still just Lattice, though word is out about a Xilinx reverse engineering effort that is getting further along.

20201126/https://www.ktemkin.com/exploring-open-fpga-hardware/

Wow, hospitals systems are really getting under strain now, rural hospitals sending their sickest patients to larger, better-resourced urban hospitals but they too under strain from the surage of urban patients hospitalized for COVID-19.

https://www.npr.org/2020/11/21/937448427/urban-hospitals-under-strain-as-rural-coronavirus-patients-are-sent-to-cities

Oh no! Lennart Poettering wants to systemd-ize the Unix home directory system? Not only is this unnecessary, it’s going to end poorly by making Unix home directories unnecessarily tedious for little people, while the big institutions are going to just keep using nsswitch to apply their own personal favorite of SSS (only used by Red Hat), LDAP (used by almost everyone), vas3 (used only by a few obscure large institutions), and others.

20201123/https://thenewstack.io/systemds-lennart-poettering-wants-to-bring-linux-home-directories-into-the-21st-century/

Well, the EOMA 68 laptop is still waiting on production bottlenecks. In the meantime, there is this other competitor that popped up, the Pinebook Pro. This is an Open Hardware laptop much more in the conventional form factor for laptop computers. But, the caveat? I really liked the approach of hte EOMA 68 of having a small, standard “computer card” board. It’s what feels would be a most natural extension from Raspberry Pi. Alas, this Pinebook Pro appears not to take that approach, instead they put the SoC straight on their own custom printed circuit board. So, thinking long term, the kinds of maintenance troubles you’re accustomed to with conventional laptops? You’ll get that here too.

Also, the form factor, they went with the super slim magnesium black metal form factor that is popular nowadays. I personally dislike it for the implications it has on a computer board that is impossible to repair without specialized tools.

20201123/DuckDuckGo pinebook pro
20201123/https://www.pine64.org/pinebook-pro/
20201123/https://www.pine64.org/2019/07/05/july-update-all-about-the-pinebook-pro/
20201123/https://wiki.pine64.org/wiki/Pinebook_Pro

A string of failed searches brought up some interesting results today.

20201123/DuckDuckGo why are proprietary textbooks so popular
20201123/https://angelinakalahari.com/blog/romance-novels-popular/

Romance novels are the most popular fiction book genre ever? Interesting. But more interesting is the commentary that this is probably one of the few art forms created by women, for women. Well, that being said, 20% of the readershsip is men, but many of these men are highly secretive about their participation. Half of all romance novel readers are married.

DuckDuckGo why aren’t more public domain books used in school

Yeah, there was that really big scare tactic to ban mention of Christmas break from public schools, and then many were thinking this meant you weren’t allowed to talk about Christmas either. Okay, fine, working through the logic, it works like this. The school is not stating it is officially sanctioning a break for Christmas, it can only officially say that there is a break because they decided so. But that’s not to say they can’t indicate the existence of any religious observance days on their calendar. And, they can make legal disclaimers if there are questions about it. Even Bill Clinton issued a memo to defend the validity of religous expression in schools.

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I decided that for my first electronics project, I wanted to use “standard logic” chips for all the needed glue logic rather than using programmable logic like a GAL or FPGA because that was one less skill needed for hardware prep, and one less thing to go wrong in the field.

But, the biggest problem I’ve ran into for this: How do I simulate my glue logic to verify it? I have the schematic design, but I was at loss on how to simulate it. KiCad has an internal circuit simulation tool, but it is only for simple dsicrete logic, nothing like digital integrated circuits.

So really, I got thinking, circling back to FPGA land, really. I wrote and simulated Verilog before as part of a college class without any actual hardware programming, would Verilog be a good grounds for simulation of this? And, now that I’ve got involved in this vintage Macintosh hardware recreation project, I can attest that it is in fact a good idea for the sake of glue logic.

Okay, so time for web searching. I cursory search found a few candidates, though some of this stuff is pretty recent.

20201122/DuckDuckGo standard logic 7400 verilog
20201122/https://github.com/TimRudy/ice-chips-verilog

Ice Studio you mention? Oh, interesting, trying to make FPGA development as easy as possible, all using open-source tools. And this FPGA Wars site, well that’s a pretty interesting name. Attack on the proprietary FPGA platforms.

Read on →

Out of the few times I’ve looked to buy an old book on Amazon, I see a very high price listed to buy the book new. Why is that? Is it really that they are doing print-on-demand for you to buy a new book? No, absolutely that’s not how it works. The book really is out of print, it’s just that there are some professional book sellers who have new-old-stock (NOS) books where they can still make a claim to the book being “new.”

So, here’s where things get interesting and very specific to Amazon. These large book sellers are primarily looking for a quick way to empty their inventory, so they try to complete these sales as quickly as possible. Amazon provides this really nice AI-driven price-setting automation scheme to streamline this process, taking into account raising the price of rare books. Also, Amazon makes it real easy for third-party sellers to be listed together on a single prroduct page./

So, that’s how the forces play together to show high prices to buy the book new. No, it is not really “new” as in newly manufactured in the last few years, here “new” is solely applied as a legal de jure term.

Read on →

Okay, network mayhem! High system CPU usage within the main router, and this is interfering with the ability of user-mode processes to run. And the most jarring issue, the fact of the matter is that for this particular problem, this looks to be caused… almost entirely internally? Well, the point in hand is that something buggy is going on with IPv6 protocol responses, but there’s not a significant amount of network traffic being generated. At least not externally, like it is all going internal but we don’t know where?

But, good news, just do /etc/init.d/network restart and all is fine. It took a real long time to run the command with the user-mode CPU starvation, but after running it, all was well.

Just remember, this command is the best one to run when the network has gone wild. And don’t worry, it is designed to never disconnect the local IP address, so if it fails, you will still be able to login locally for administrative purposes. Just that it will restart all services. Best method is to do this, trying to restart sub-services piecemeal like dnsmasq, odhcpc, dropbear, etc. usually doesn’t go too well because it creates other conflicts.