isopede

2 tháng trướcdiscuss

Does regenerative braking work with a motor like this?

7 tháng trướcdiscuss

Yeah, afaik arhitecture dynamic binary translation dates back to at least 1998 (VMware).

If you leave out the JIT part, binary translation dates back to at least 1966 (Honeywell).

Still one of the GOATs, agree.

isopede

7 tháng trướcdiscuss

Look, my setup works for me. Just add an option to reenable spacebar heating.

isopede

8 tháng trướcdiscuss

I have such fond memories of the Nokia N810.

I did my master’s thesis on that device. I had a custom hypervisor running a guest kernel, virtualized networking, and a buildroot userspace. I could SSH into the host N810, then SSH into the guest. I even virtualized the framebuffer at some point and got the “dancing baby” animation playing from the guest. It only ran at a couple frames per second, but it was _amazing_.

isopede

10 tháng trướcdiscuss

It's been a few years since I last looked at it, but I've tried daily running it probably 4 or 5 times over the last 15 years. Usually on Arch, but also some Debian/Ubuntu-based distros. It's fuzzy now but I've tried probably every NVIDIA GPU generation since the GTX 500 series.

I can't remember all the bugs, but I've definitely at least encountered all flavors of flickering bugs, stale updates, GPU crashes, failed copy and paste, failed screenshares, failed videoconferences...

From comments on this thread, it sounds like things have drastically improved and its probably time to take another look.

isopede

10 tháng trướcdiscuss

Somebody sell me on these newfangled tiling WMs. I have been using basically the same xmonad configuration for 15+ years, pretty much updating it only on breaking or deprecated changes. What do all these new Wayland compositors have to offer except "tiling, but for wayland?"

Does Wayland actually work now? I've tried it every few years for over a decade now and every time I ran into showstopper bugs (usually on nvidia cards).

isopede

11 tháng trướcdiscuss

I strongly believe that we will see an incident akin to Therac-25 in the near future. With as many people running YOLO mode on their agents as there are, Claude or Gemini is going to be hooked up to some real hardware that will end up killing someone.

Personally, I've found even the latest batch of agents fairly poor at embedded systems, and I shudder at the thought of giving them the keys to the kingdom to say... a radiation machine.

isopede

11 tháng trướcdiscuss

Neat. Anyone know what is used to make the animations? I like the graphic design!

isopede

năm ngoáidiscuss

That band is often chosen _because_ of the absorption band of oxygen. Significant attenuation at those frequencies means it limits range, allowing for higher frequency reuse and less interference over a greater area.

isopede

2 năm trướcdiscuss

Interference is a real problem with FMCW radars, either maliciously in the case of electronic warfare, or accidentally in the case you mentioned, with many radars in the same space using the same frequency band. Wifi and cell phones use time division or frequency division multiplexing techniques, but radars (at least current-gen) generally do not.

There are mitigation techniques like randomization of chirp frequencies, choosing different idle times between frames, and signal processing techniques to try to detect interference and filter it out. In the general case, FMCW techniques will always have interference problems.

This is one reason amongst many others that military radars do not use FMCW but instead coded pulse compression techniques.

isopede

2 năm trướcdiscuss

Is it though? I can run Windows programs from 20 years ago on my Windows machine just fine.

Issues with Linux binary distribution meanwhile are ubiquitous, with glibc probably being the single biggest offender. What's worse is that you can't even really statically link it without herculean effort. I've spent an inordinate amount of my life trying to wrangle third-party binaries on Linux libraries and it's just a sorry state of affairs.

Try taking a binary package from a vendor from even just 5 years ago and there's a non-zero chance it won't run on your modern distro.

isopede

2 năm trướcdiscuss

Among other things, tooling and vendor libraries. Vendor libraries are often composed of thousands upon thousands of lines of auto-generated C headers and written in some bespoke format. Demonstration code and/or sample drivers are almost invariably provided in C. Of course you _can_ rewrite these in Rust, but if you're an engineer trying to get shit working, you'd first basically have to reinvent the whole wheel just to do bringup.

I don't even want to talk about the state of proprietary vendor tooling...

isopede

2 năm trướcdiscuss

C++ has long surpassed the point where mere mortals like me can understand it; It's so loaded with baggage, footguns, and inscrutable standards language that honestly I think the only thing keeping it going is institutional inertia and "backwards compatbility" (air quotes).

I work extensively in the embedded space and unfortunately C and C++ are still pretty much the only viable languages. I can not wait until the day rust or some other language finally supplants them.

isopede

2 năm trướcdiscuss

I don't understand the backlash outside some sort of weird "anti-woke" attitude. Even ignoring all the problematic history, the Lena image hasn't been a good test image for years. It's a 512x512 scan of printed CMYK dots and not particularly representative of the types of files and images we share today. This was true even twenty years ago when I myself was using this test image to do wavelet transforms.

It's time we moved on.

isopede

2 năm trướcdiscuss

I tried it a few months ago, back in November.

I looked through what I did and in the end, to bring in pw_result, I had to define a failure handler, pull in three separate cmake files for various definitions, define an ASSERT action (because a result type requires an ASSERT fail, apparently?), and set a backend and a handler for pw_assert. At some point I remember it complaining left and right about not having the right I/O methods for printing, etc. I just wanted to try the result type, and for some reason I needed to define I/O mechanisms for my platform.

Is this the correct procedure? I have no idea, because the cmake documentation had (has?) _zero_ examples. If they existed, I couldn't find them. I eventually got it to compile with the following snippet, but I can hardly believe that this is the "intended" way to do it.

  FetchContent_Populate(pigweed)

  include(${pigweed_SOURCE_DIR}/pw_build/pigweed.cmake)
  include(${pigweed_SOURCE_DIR}/pw_assert/backend.cmake)
  include(${pigweed_SOURCE_DIR}/pw_assert_basic/backend.cmake)

  add_compile_definitions(PW_ASSERT_BASIC_ACTION=PW_ASSERT_BASIC_ACTION_LOOP)
  pw_set_backend(pw_assert.check   pw_assert_basic.check_backend)
  pw_set_backend(pw_assert.assert  pw_assert_basic.basic_handler)

  add_subdirectory(${pigweed_SOURCE_DIR} ${pigweed_SOURCE_DIR})

isopede

2 năm trướcdiscuss

I don't think fiber cables are expensive. I ran CAT6 in my house and at the same time pulled an OS2 single-mode 30m fiber cable to my office for core switching. The 30m fiber cable was $17 on Amazon, plus two 10G-LR modules at $18 each. The equivalent CAT6 is more power hungry, has less range, the cable is the same damn price, and the 10GBase-T SFP->RJ45 transceivers are twice the price of the LR transceivers at $50 each.

isopede

2 năm trướcdiscuss

I tried to evaluate pigweed a little bit by importing just a single module (pw_result) into my existing CMake-based MCU project. I guess you guys technically do have support, but it seemed unnecessarily difficult to pull in. Just pull the source code in, and link against pw_result right? Nope. I ended up having to spend a few hours working out what the heck facades are, various handlers for I/O, implement my own crash handlers, all the while having to poke through/model existing handlers that had "DO NOT USE IN PRODUCTION" written all over it.

I did end up getting it working, but it was clear that GN/Bazel is the blessed build system and CMake is just an afterthought.

In contrast, I pulled in expected-lite [1] with a single line of CMake's FetchContent, #include'd the header, and it just worked.

[1] https://github.com/martinmoene/expected-lite

isopede

2 năm trướcdiscuss

I have a rather extensive homelab, painstakingly set up over time. It works great, I love it. Few questions for you guys:

- My real problem is disaster recovery. It would take me forever to replicate everything, if I could even remember it all. Router configurations, switch configurations, NAS, all the various docker containers scattered across different vlans, etc. I mapped out my network early on but failed to keep it up to date over time. Is there a good tool to draw, document, and keep up-to-date diagrams of my infra?

- Backup and upgrading is also a persistent problem for me. I will often set up a container, come back to it 6 months later, and have no idea what I did. I have dozens of containers scattered across different machines (NUCs, NAS, desktops, servers, etc). Every container service feels like it has its own convention for where the bind mounts need to go, what user it should be run as, what permissions etc it needs. I can't keep track of it all in my head, especially after the fact. I just want to be able to hit backup, restore, and upgrade on some centralized interface. It makes me miss the old cattle days with VM clone/snapshot. I still have a few VMs running on a proxmox machine that is sort of close, but nothing like that for the entire home lab.

I really want to get to a point, or at least move towards a solution where I could in theory, torch my house and do a full disaster recovery restore of my entire setup.

There has to be something simpler than going full kubernetes to manage a home setup. What do you guys use?

isopede

2 năm trướcdiscuss

In fact there is! It's called a Gomboc:

https://en.wikipedia.org/wiki/G%C3%B6mb%C3%B6c

isopede

2 năm trướcdiscuss

I like to solve this problem in Kerbal Space Program simply by avoiding it:

My landers are designed to land sideways.

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