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1. Embed this notice
   Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 23-Dec-2024 17:52:12 JST Foone🏳️‍⚧️

   I wonder if there'd be any electrical problems with wiring together two picos as USB devices, which are both plugged into the same computer.

   Like it's obviously okay if they're on the same hub, but different hubs? I don't know but I wouldn't be surprised if that's an issue.

   • Embed this notice
     Rich Felker (dalias@hachyderm.io)'s status on Monday, 23-Dec-2024 17:52:10 JST Rich Felker

     in reply to

     @foone Semantically as single multifunction device, I dunno. But it's always possible to have the device be "USB hub" with 2 virtual keyboards connected.

   • Embed this notice
     Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 23-Dec-2024 17:52:11 JST Foone🏳️‍⚧️

     in reply to

     actually, I wonder... is it possible to have a USB device identify as multifunction, but those functions are "two separate keyboards"?

   • Embed this notice
     Rich Felker (dalias@hachyderm.io)'s status on Monday, 23-Dec-2024 17:52:57 JST Rich Felker

     in reply to

     @foone It's possible to get ground loop issues with USB if electrical stuff isn't done right.

   • Embed this notice
     Rich Felker (dalias@hachyderm.io)'s status on Monday, 23-Dec-2024 18:02:07 JST Rich Felker

     in reply to

     • Wilfried Klaebe

     @wonka @foone Is there a hard limit on number of hubs?

   • Embed this notice
     Wilfried Klaebe (wonka@chaos.social)'s status on Monday, 23-Dec-2024 18:02:08 JST Wilfried Klaebe

     in reply to

     • Rich Felker

     @dalias Unless that would make too many hubs.

     @foone

   • Embed this notice
     Rich Felker (dalias@hachyderm.io)'s status on Monday, 23-Dec-2024 18:03:06 JST Rich Felker

     in reply to

     • Wilfried Klaebe

     @wonka @foone I mean, if there is, there's probably some awful way to do "USB connected PCIe bus interface" and "USB controller on PCIe" to nest it further.. 🤪

   • Embed this notice
     Rich Felker (dalias@hachyderm.io)'s status on Monday, 23-Dec-2024 18:37:40 JST Rich Felker

     in reply to

     • Wilfried Klaebe
     • Jernej Simončič �

     @jernej__s @wonka @foone That seems like a limitation of the host controller implementation not the actual bus. The bus isn't really capable of knowing the total number of devices AFAICT (but could know the hub depth as part of addressing).

   • Embed this notice
     Jernej Simončič � (jernej__s@infosec.exchange)'s status on Monday, 23-Dec-2024 18:37:41 JST Jernej Simončič �

     in reply to

     • Rich Felker
     • Wilfried Klaebe

     @dalias @wonka @foone IIRC, with USB2 you can't have more than 7 hubs (and a total of 127 devices). No idea about USB3, but I know that it's limited to 31 devices.