Mastodawn

Mäh W.

@maehw@chaos.social

359 Followers

732 Following

3.5K Posts

👨‍💻 I am interested in wired & radio communication, DSP, (embedded) software dev & engineering, FOSS, reverse engineering, IT security, space, programmable and non-programmable bricks, old and new computer technology, robots, machine embroidery & other things. Living in 🇩🇪. Speaking 🇩🇪/🇬🇧/💻 and understanding a little bit of 🇫🇷.

@funkylab And therefore I wasn't going to open it anyways. Just in case I'd plan to do the soldering.

@funkylab well, there will quite likely be some sort of dumb (probably multi-port) USB 5.0V power supply anyway. I'd only hot glue a USB cable to the socket of the device and not the whole housing itself, which will keep the AP modular and movable.

This is the thingie!

Wobbly micro USB connector supplying power to this tiny WiFi access point. It's a slack joint. Photo in the next toot.

🧵

	Hot glue to the rescue!
	Open it and re-solder!
	Other (comment below)

Poll ends at 6:16pm.

Cliff Maier 1d ago

@tjw On the day Opteron was supposed to tape out, a colleague discovered a logic bug. After some analysis, we figured out we could fix it by disconnecting a wire from one gate and attaching it to another. But running through or design flow would take days, and the ripple effect of changing connectivity could cause more problems. So I loaded the chip mask into VIM and modified the polygons directly, then we taped it out.

Don’t remember for sure, but I don’t think we told management 🙂

@GuyBirkin Nice photograph! "Crown shyness" came into my mind: https://en.m.wikipedia.org/wiki/Crown_shyness

Crown shyness - Wikipedia

Adam Zeloof 3d ago

I reverse engineered the firmware loading utility of a $17 beauty salon spectrophotometer to load the firmware of its "big boy" sibling:
https://adam.zeloof.xyz/2025/07/10/x-rite-pantone-spectrophotometer-unlock/

Eric Brombaugh 1d ago

A few years back I did some reverse engineering on the original Alesis MIDIVerb. I've released the design materials and source code that came out of that effort here: https://github.com/emeb/MIDIVerb_RE

GitHub - emeb/MIDIVerb_RE: Reverse-engineering the MIDIVerb audio effects processor

Reverse-engineering the MIDIVerb audio effects processor - emeb/MIDIVerb_RE

GitHub

mem_somerville 4d ago

Y'all remember that lace safety vest that a cyclist was wearing a while back? Everyone sent it to me because #Lace .

I had no idea where it came from, but I loved it. Recently a vendor of them popped into my feed. I decided to try one to see if it was legit.

It's very nice. I'm not selling them, I'm not pushing them, I'm just saying if you like to lace in safety now you can....

I'm kind of impressed with the quality.

adlerweb // BitBastelei 4d ago

Kollege hat darauf hingewiesen, dass quasi alles an #Lötpaste von #AliExpress & Co verschwunden ist. Jemand auf dem Schirm, ob sich da was geändert hat?

×

✧✦Catherine✦✧Jun 29

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

✧✦Catherine✦✧Jun 29

there's actually a few loops in the middle doing the same memcopy operation. i think the compiler smokes crack

✧✦Catherine✦✧Jun 29

although, a horrifying thought is that this is just what the original code looked like

✧✦Catherine✦✧Jun 29

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:
https://en.ktjmyq.com/html/2024/MEMS_0526/141.html

KT-EX9-1 - MEMS GYROSCOPE - KaiTuo Precise Instrument Co., Ltd-accelerometer,Gyro,MEMS,MEMS Gyro,MEMS Accelerometer,KTJB1,KTFG,KTEX

FEATURESTriaxial, digital gyroscope, ±450° sec dynamic range ±0 05° orthogonal alignment error,0 3&

✧✦Catherine✦✧Jun 29

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?

SDRHoernchen Jun 30

@whitequark.. Or just a shady copy of a copy, due to usage? Returns probably happen rarely, and the buyer might be a bit desperate.

✧✦Catherine✦✧Jun 30

@SDRHoernchen it's possible, but I think it's somewhat unlikely

Timon 🛠Jun 30

@whitequark One off'ish feels kinda likely. I seen that a few times in the med space despite doing that only briefly. Some sub-assembly was unobtainable so a shoddy "drop-in" that only replicates the features the specific device was using was made as it was easier/cheaper than redesigning the device itself.
Prob. not too different in the defense space?

✧✦Catherine✦✧Jun 30

@timonsku yep, that's my guess; no reason to try and name the firmware to impersonate some other vendor

Philip Guenther Jun 30

@whitequark I’m fine with compilers NOT being responsible for all the final code sins of the world

Timon 🛠Jun 30

@whitequark going full time freelance has truly opened my eyes when it comes to the state of software in the embedded space. I always assumed that I write mediocre code at best but the bar for "ready to ship" is in fact so much lower than I could have ever imagined

✧✦Catherine✦✧Jun 30

Joel Michael Jun 29

@whitequark * Keil has entered the chat

Aaron Sawdey, Ph.D.Jun 30

@whitequark a frequent problem with compilers, actually. Sometimes it doesn’t even involve UB 😂

Joel Michael Jun 29

@whitequark lolololol amazing, I guess they’re not using assembly for their init handler

✧✦Catherine✦✧Jun 29

@jpm this firmware is weird

Tóth Gábor Baltazár Jun 29

@whitequark
that is indeed a fun roll :3

Kevin Riggle Jun 29

@whitequark putting the fun back in -funroll-loops

@whitequark I would definitely want my loops to be fun rolled, tbh