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If diy doesn’t work I’ve been using loud bicycle horn and it works great. https://loudbicycle.com/ https://loudbicycle.com/

by kfarr 6mo ago

philips 6mo ago
Gah! mini usb instead of USB C. Love the concept but it is remarkable how long bike accessories have been holding out on USBC.
- vscode-rest 6mo ago
  At least they’re forward about it - I’ve lost count of how many bike accessories claimed to be USB C, but they only charge when connected to their specialized cable that converts from USB A to C.
  - hnuser123456 6mo ago
    Double-sided USB-C connections require a handshake before sending voltage. USB-A ports can have the 5v line active at all times. Cheap USB C gadgets often don't make the handshake, they just use it as a 5V input, necessitating an A to C cable.
    - vscode-rest 6mo ago
      Interesting. Does UsBC spec/licensing require any sort of notation for products that don’t implement handshake?
      - bmicraft 6mo ago
        There is no handshake, all that's needed are two 5.1 kΩ pulldown resistors. By omitting them the manufacturer saved all of about 0.1c and made their device incompatible with compliant usb-c chargers. More info: https://hackaday.com/2023/02/07/all-about-usb-c-manufacturer-sins/ https://hackaday.com/2023/02/07/all-about-usb-c-manufacturer...
      - auguzanellato 6mo ago
        Such products shouldn’t exist by spec, they’re just not compliant.
    - alacritas0 6mo ago
      If you add 5.1kΩ pulldown resistors on the CC lines for USB-C, you can get the standard 5V without a handshake although current may be limited by some chargers without negotiation.
    - hdgvhicv 6mo ago
      One of the many deficiencies of usb-c (who knows what power your cable supports, charger supports, if you accessory will charge, of it will connect at all)
    - amstan 6mo ago
      I think you're overstating this. The "handshake" is purely 2 simple resistors correctly installed. The problem is a lot of folks do it wrong for various reasons, most likely never testing with anything more than type a to type c cables. https://people.kernel.org/bleung/how-to-design-a-proper-usb-c-power-sink-hint-not-the-way-raspberry-pi-4 https://people.kernel.org/bleung/how-to-design-a-proper-usb-...
    - NooneAtAll3 6mo ago
      I'm still waiting on full-size usb-c instead of current mini-usb-c
case 6mo ago
I’ve got one of these fwiw, and it’s outstanding.

If diy doesn’t work I’ve been using loud bicycle horn and it works great. https://loudbicycle.com/ https://loudbicycle.com/

by kfarr 6mo ago

If diy doesn’t work I’ve been using loud bicycle horn and it works great. https://loudbicycle.com/ https://loudbicycle.com/

philips 6mo ago

Gah! mini usb instead of USB C. Love the concept but it is remarkable how long bike accessories have been holding out on USBC.

vscode-rest 6mo ago
At least they’re forward about it - I’ve lost count of how many bike accessories claimed to be USB C, but they only charge when connected to their specialized cable that converts from USB A to C.
- hnuser123456 6mo ago
  Double-sided USB-C connections require a handshake before sending voltage. USB-A ports can have the 5v line active at all times. Cheap USB C gadgets often don't make the handshake, they just use it as a 5V input, necessitating an A to C cable.
  - vscode-rest 6mo ago
    Interesting. Does UsBC spec/licensing require any sort of notation for products that don’t implement handshake?
    - bmicraft 6mo ago
      There is no handshake, all that's needed are two 5.1 kΩ pulldown resistors. By omitting them the manufacturer saved all of about 0.1c and made their device incompatible with compliant usb-c chargers. More info: https://hackaday.com/2023/02/07/all-about-usb-c-manufacturer-sins/ https://hackaday.com/2023/02/07/all-about-usb-c-manufacturer...
    - auguzanellato 6mo ago
      Such products shouldn’t exist by spec, they’re just not compliant.
  - alacritas0 6mo ago
    If you add 5.1kΩ pulldown resistors on the CC lines for USB-C, you can get the standard 5V without a handshake although current may be limited by some chargers without negotiation.
  - hdgvhicv 6mo ago
    One of the many deficiencies of usb-c (who knows what power your cable supports, charger supports, if you accessory will charge, of it will connect at all)
  - amstan 6mo ago
    I think you're overstating this. The "handshake" is purely 2 simple resistors correctly installed. The problem is a lot of folks do it wrong for various reasons, most likely never testing with anything more than type a to type c cables. https://people.kernel.org/bleung/how-to-design-a-proper-usb-c-power-sink-hint-not-the-way-raspberry-pi-4 https://people.kernel.org/bleung/how-to-design-a-proper-usb-...
  - NooneAtAll3 6mo ago
    I'm still waiting on full-size usb-c instead of current mini-usb-c

case 6mo ago

I’ve got one of these fwiw, and it’s outstanding.