Last Night's General Meeting Decompression and Next Month

[camp .]

    What a great meeting last night! Thanks to David Schulof and Toborlife for hosting us. Thanks to Nathan Lewis for presenting the BotPDU (Power Delivery Unit), to all the folks who showed up, and especially to those who participated in Show-and-Tell.

    March is our HBRC Challenge month "Phase I."* It will be our 24th Annual, so get your robot running! If you're not currently building, start! Your deadline is the last Wednesday of the month... March 25th.

Challenges

https://www.hbrobotics.org/index.php/challenges/

Thanks,

Camp

* HBRC Challenge Phase I: Bring your robot in some state of "finished."

[Ross Lunan]

Perhaps this was covered by Nathan's presentation which I unavoidably missed: On the ROS Tue evening Feb24 PD subject in a brief exchange, to followup here is a Pinout diagram showing the USB-C 12 Pin assignments x2 for reversal, and a transcription from Gemini on PD DataPins CC1 & CC2 function. Illustrates why it's essential to select a "PD Compliant cable" to power a RP5 in PD mode.  Ross

USB-C what are PD data pins?

USB Power Delivery (PD) data is transmitted over the Configuration Channel (CC) pins (CC1 and CC2), not the USB 2.0 or data pins. A single CC pin is used to communicate between devices to negotiate power contracts, enabling up to 240W (48V/5A). The other CC pin can act as VCONN to power the cable’s e-marker chip.

Key Details About PD and USB-C Pins:
CC1/CC2 (Configuration Channel): These are the primary pins for PD, handling orientation detection, cable identification, and power negotiation.

Data Transfer vs. PD: While PD uses the CC pins for negotiation, actual data transfer occurs on the TX/RX pairs (High-Speed) or D+/D- pins (USB 2.0).

E-Marker Communication: The PD protocol uses the CC lines to read e-marker chips in the cable to determine cable capabilities (power rating, speed, etc.).

Reversibility: Only one CC pin is used at a time, allowing the connector to be flipped.

Power vs. Data Cables:
Full-featured Cable: Includes 24 pins for power (VBUS/GND), CC, and all data lanes (USB 3.x/4).
Charge-only Cable: Often reduces pin count to only 4 (VBUS, GND, and CC) to reduce cost, but still requires the CC pin for proper PD negotiation.

[Pito Salas]

I struggled with identifying my USB cables, not just PD vs. Non-pd but also USB2.0 USB2.1 etc.) This was while I was trying to get my Oak-D-Lite to work.

I found this little device which was very helpful. It’s not too expensive and it does a lot more. For me it was a life saver!

This might be of interest.