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I use two of these clocks daily at work, to synchronize a high-speed process on video. I'll be buying a couple more.


How well synchronized are the updates of the two displays?


Assuming any decent GPS signal at all, they should be well within 1ms of each other, likely a bit better.


A cheap GPS module without a disciplined 1PPS output (like the ublox MAX-M8 that's used in this project) typically has a jitter of about a few hundreds nanoseconds, so the potential is there for the precision to be much better than 1ms if the microcontroller on this clock has the 1PPS wired to an interrupt routine.


> jitter of about a few hundreds nanoseconds

The 1PPS output may have that much jitter (due to it being clocked synchronously with the module's system clock) but I believe there is usually a way to query the device for the error between the 1PPS signal and the actual idealised pulse time.

Sylvain Munaut made a project using a high resolution TDC/time of flight converter to discipline another clock against the GPS idealised pusle time. I can't find a link right now unfortunately.


Yes, this feature exists, but it's usually only present on GPS modules that are sold specifically for time keeping instead of location tracking, such as the uBlox LEA-M8T.

They are much more expensive, think $100 instead of $10.


That it does.

Should be within tens of ns if you have good reception and decent antenna placement.


In a previous life, with a specific set of hardware, we used a measured value of 70 ns two sigma as the typical skew between two GPS-disciplined clocks. Don’t use these numbers without testing your own system, but confirms order of magnitude estimate.


Needs more exclaimation points!


this looks great!


Penrose looks great. Beautiful diagrams and readable code. What are some other text-driven diagramming languages / tools? I know of:

https://mermaid.js.org/ https://graphviz.org/ https://flowchart.fun/


D2 is my current favorite: https://github.com/terrastruct/d2


D2 is scripting language primarily for non-free back-end. Opensource back-ends give inferior results with it.



Mermaid has been nice to use. It's very much in a beta phase still, with some odd quirks and missing documentation. I'm excited to see where it will be in a year's time.


The fact it's supported natively by GitHub gives it a huge advantage over the others.


In GitLab too


MetaPost. Shameless plug for my own introduction page: http://www.learnmetapost.com



Another approach may be https://google.github.io/typograms/

Anyway, I think that mermaid.js have an advantage there in a lot of environments as it is supported by a lot of markdown renderers, I would like that ChatGPT one does that too.


I assume the future is an LLM where you specify everything in plain english...


yup but ... right now things are in a bit of a primitive state.

i have tried a lot of stuff with the ChatGPT Wolfram integration and it just fails all kinds of ways. its really cool when it works, but a lot of time it just gets really confused and cannot do basic things like "make that line black instead of red"


it already works really well with gpt4+mermaid.


Tikz


Asymptote[0] is excellent IME.

[0] https://asymptote.sourceforge.io/gallery/


For quick flowchart I use https://www.websequencediagrams.com/


Here's a page listing several more: https://text-to-diagram.com/


This page was made by the company behind D2, so not exactly an unbiased source.



D2 Lang is a nice one:

https://d2lang.com/


The horse used the elevator? I didn't know he knew how to do that.


Hey, he was one of main answers in today's NYT Sunday Crossword today. Probably coincidence.


Pardon the "Snappy Answer...," but the NYTimes Sunday Crossword not only has Al Jaffee as the keystone theme answer, but all the other main answers are humorous inventions in his comics that in fact became reality years later. In particular: Automatic Redial on telephones (1961), Spell Checkers ('67), Snowboarding ('65), Three-blade razors ('79), and Graffiti-proof Buildings ('82).

I haven't independently verified these, but I do recall other items that appeared as jokes in Mad, and later turned up for real: "Shpratz(sp?)", a spray to give your car the "new-car smell"; also an unnamed device that would keep your car from running if you weren't paying attention to the road (as depicted, for instance, because you were ogling someone you were passing on the sidewalk, though come to think of it, maybe it just snapped your head back to face forward).


> Hey, he was one of main answers in today's NYT Sunday Crossword today. Probably coincidence.

For his hundredth birthday? Sounds less like a coincidence and more like a tribute.


Not a coincidence. It rarely is, the crosswords are chosen pretty deliberately. In general, if you want the back story to a crossword in the NYT, they have a column - in this case, https://www.nytimes.com/2021/03/13/crosswords/daily-puzzle-2...


I do The NY Times crossword every day. As stated it’s very much not a coincidence. The puzzles tend to be timely. They also tend to build on each other so doing them regularly make the weekend puzzles more doable too.

Note for anyone not familiar The NY Times crosswords build in difficulty through the week. Saturday is actually the most technically challenging. Sunday’s is the biggest. Thursday’s usually have some sort of trick you need to figure out like a rebus square (takes multiple letters in a single square) or answers that wrap around.


I switched to croc (https://github.com/schollz/croc) to send large files. Works great across macOS and Windows. It's synchronous, one-time, so not a fire-and-forget system. But quick for large files (sending custom disk images for Raspberry Pi).


Tried using: set my Meraki to serve up the IP address given by the dashboard. The my.nextdns.io dashboard says something like "this device is using a different configuration with nextdns".

I think it happens after you configure an anonymous DNS, then you create an account. It feels like my configuration got disconnected or something. Hard to describe.

Regardless, the blacklist/whitelist didn't work. Maybe a caching problem? Will try back later.


The router, os and browser can cache so whitelist takes a while


Totally agree on this. I've build heaps of production code using xsv. Far faster than csvkit and more features.


Because ripgrep is the reason I discovered Rust (along with xsv for CSV manipulation) and because Andrew asked:

% grep "die()" * [...results with functions named die()...]

% rg "die()" Error parsing regex

I reach for grep when I need to do non-regex searching. Can't remember how to do an fgrep fixed-pattern style ripgrep.

great tools andrew: I use them every day and install them first thing on a new box. know that your code really helps


Ah yes! That is a good one too. That's because grep uses "basic" regexes by default, and this sort of use case is one area where they work nicely. The downside is needing to remember which meta characters need to be escaped.

For ripgrep, you can enable literal search the same way you do it in grep: with the -F flag.

Thanks for responding!


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