Sebastian Krzyszkowiak @dos@librem.one

@martijnbraam I considered that, but eventually decided against:
a) CH342 has an integrated LDO; BOM wouldn't get shorter by getting rid of it
b) this way UART channel works regardless of what you're doing in firmware; one less thing to care about
c) there are free samples available for STM32G071CBT6; no samples for USB-equipped G0B1/G0C1 😄

@ge0rg It's somewhat common in DIY designs, badges etc. although those usually don't require any PD stuff. MacBooks can expose 1.2V UART, I2C and debug USB - you could use Debubo paired with SBUB to access that. And who knows what undocumented commands to mux things onto SBU may be in other devices out there 😁

@eliasr Nope; with Debubo (and a right TPS65982 config) you can access UART console, while also connecting a charger or some USB thingy, either host or device.

But what you described is pretty much just a regular USB-C hub with PD 😁

The hardware design is now released at https://gitlab.com/dos1/debubo

#debubo #kicad #diy #electronics #librem5 #stm32 #usbpd #oshw

@forteller Thanks for sharing! I was looking for a GTK4 app just like that to steal its UI from 😈

@martijnbraam Found a bug!

I have two part numbers for the same value & footprint:

C5, C2 1µF 1206 C1966364, C24497

The first one matches, the second one does not (it's 100nF) - but partlint doesn't report a problem with the second one until I remove the first one.

Nice tool and timing, you pushed it just in time for when I needed it 😁

@nokernel Yes, used it a lot! There were many more bridges at first 😂 Got rid of all the rest, but this one is highly resilient.

TBH, it's the first time I solder such tiny things, it's a wonder I got as far as I did already anyway :)

Joints seem to be better now, but I didn't mention one thing - no matter how much hot air I blow at it or what I do with soldering iron, I can't seem to be able to get rid of a short between D+/D- on a passthrough port 😭 It's not critical, the important parts are already operational, but it would be nice to get USB 2.0 passthrough working too! I'm assuming it's on the USB-C plug, but it all looks perfectly fine to my eye 😫 I should finally get some proper flux I guess... #soldering #diy

Took me 3 days of soldering, but it works!

I can connect it to a Librem 5 and it automatically does all the needed PD stuff to expose its UART over USB-C 😁 It's also capable of a lot of other PD magic as a USB PD analyzer / injector / filter.

However, while these solder joints made a good job lasting till I got the firmware PoC working, it doesn't seem like they're going to last much longer... More soldering ahead 😫

#debubo #kicad #stm32 #usbpd #librem5 #shotonlibrem5 #diy #electronics #oshw

@alaraajavamma @MissBehave @PINE64 You may have to load module-bluetooth-policy in PulseAudio to have it switch to HSP automatically - but you can also switch manually in the settings. Otherwise - yep, as long as you can connect to your Bluetooth device it should just work.

@alaraajavamma @MissBehave @PINE64 No, with normal cellular calls. In fact, there's no difference on Librem 5, as modem's audio is just another digital audio interface seen by ALSA.

@alaraajavamma @MissBehave @PINE64 BT call audio worked for ages on the Librem 5 (with SparkLAN card - Redpine does not support HSP, which is a bit of a hurdle 😜).

@ptrc I had to adjust open files ulimit on my system because I regularly ran out due to terminal tabs.