whitequark.org
catgirl shaped object
"A cat is valued for companionship and its ability to kill vermin."
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i'm wrong. the KT-EX9-1 device has a public datasheet and some key values don't match
this could be a custom one-off or something?
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OH I GOT IT
i finally tracked down the source of this device, and also the gyroscope vendor
the WM_KT-EX9-10_2.12_GD103.bin in the firmware name most likely refers to the gyro:
en.ktjmyq.com/html/2024/ME...
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although, a horrifying thought is that this is just what the original code looked like
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there's actually a few loops in the middle doing the same memcopy operation. i think the compiler smokes crack
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did someone build the firmware with -funroll-loops or what
this is a part the code that copies static mutable data into RAM from Flash. it goes on for kilobytes
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here's a firmware name: WM_KT-EX9-10_2.12_GD103.bin
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nevermind, it works fully once i attach a logic analyzer. for one reason or the other, adding a few pF of capacitance to the pins is what it needed
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it looks like sometimes it works and sometimes it doesn't
very bold of a vendor to call it a "good device" when in fact it seems to be bad
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the source code is not protected (i am reading out valid values), but for some reason my dump memory command is encountering errors; most likely a misunderstanding of ADIv5.2
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we have SWD!
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oh... it has a GD32F103 inside. there are even, conveniently, pads with SWD routed to them
firmware dumping time? firmware dumping time.
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oh yeah i just copy&paste from mastodon, oops
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i think some enterprising company (possibly Shenznen Firepower Control Co. Ltd. based on @[email protected]'s research) has realized they can make a lot of money selling ADIS16488-style devices that only barely work at a half of their sticker price from AD
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this thing doesn't seem to have a magnetometer or a barometer, it's just an accelerometer and a gyroscope. not even very good ones, they're probably on par with what your cellphone has, if not worse
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oh, i just realized that it has a "product ID" register that clearly says 0x4068 (16488). so it's supposed to be a clone of ADIS16488 then. it's just a very bad one
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the delta-angle and delta-velocity functionality appears to simply not exist, which excludes this being a faithful clone of either adis16488 or adis16375
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video uploads are broken so watch this one on mastodon mastodon.social/@whitequark/...
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this is definitely not an ADIS16488 and if it's a clone of it, then they have taken some remarkable liberties with the idea of a "functionally identical" replacement
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i spent like a hour getting it to reply anything to me
i think this qualifies
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it's alive and talking to me!
as usual, the SPI peripheral implementation in it is kinda finicky, and it actually doesn't work with the default #GlasgowInterfaceExplorer SPI controller (because it's not fully compliant with SPI, oops)
i'll fix the SPI controller in a bit
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never trust the author self-insert character
or anyone who acts like the author self-insert character, anyway
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mine is a monogatari anime
some of these plot twists are of a kind that change you forever
and not always in a good way
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general introduction: glasgow-embedded.org/latest/intro...
runnable code for the example above: github.com/GlasgowEmbed...
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oh, and of course, if you use some custom protocol the industry has never seen before, you have an FPGA that can be used to implement it.
e.g. it took me less than a week to build an RGMII Ethernet endpoint that can shuttle packets from a SoC to a TAP interface on the host
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just as easily you can add JTAG/SWD debug, protocol analyzers, etc
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i would volunteer
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evening!
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i used chatgpt because the person i talked to used chatgpt
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that sounds like bang-bang control ;;
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my condolences / best wishes
i love vapor compression refrigeration as a process to work with, but speccing out consumer systems is kind of soul-draining
do you at least get to use the ones with PID control, or is it bang-bang over in AU too?
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i particularly dislike BTU (which, to their credit, isn't originally the fault of americans) because the figure of merit for aircons is COP and it's a factor. you multiply electrical power by it to get cooling power. and i've never seen electricity be measured in BTUs
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have you ever looked up units used in HVAC
i think i've seen in the wild a unit of heat conductivity for insulation that is BTU/hr/ft^2/inch
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the first post in the thread expressed a desire to go to the grave fighting over fahrenheit. fine, doable
moreover i have a strong personal dislike of a worldview where "with science" is somehow separate from "with everyday life"
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wrong: i inferred it from the fact that you suggest using a different temperature scale
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i think the average person could stand to have more (and a more direct) connection to science, not less. i see this to be the case regardless of what you meant here
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idk, i feel like no game, no matter how odd or annoying, is objectively bad in this way
there's no wrong way to make art
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people say stuff like this as if "With Science" is something that other, unknown, mysterious people do and not like it's the foundation of our entire society for hundreds of years and the basis of its everyday functioning
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yeah