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700 points elipsitz | 6 comments | | HN request time: 0.447s | source | bottom
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nimish ◴[] No.41194268[source]
Gross, the dev board uses micro-USB. It's 2024! Otherwise amazing work. Exactly what's needed to compete with the existing giants.
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sowbug ◴[] No.41194477[source]
Perhaps the unfortunate choice of micro USB is to discourage real consumer products from being built with the dev board.
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1. user_7832 ◴[] No.41194882[source]
I wonder if it is more about simply shaving a few cents off. Full USB-C protocol implementation may be much more difficult.
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2. hypercube33 ◴[] No.41194978[source]
USB-C doesn't require anything special USB wise as it's decoupled from the versioned standard. It just has more pins and works with all modern cables. Ideally the cables won't wear out like Mini and Micro and get loosey goosey in the ports.
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3. ewoodrich ◴[] No.41195383[source]
Yep, a USB-C connector is more or less a drop in replacement for MicroUSB if you don’t need USB3 or USB-PD. With one aggravating exception: it requires adding two 5.1kΩ pulldown resistors to be compatible with C-C cables. Thus signaling to a charger that the sink is a legacy non-PD device requesting 5V.

Which is apparently an impossible ask for manufacturers of dev boards or cheap devices in general. It’s slightly more understandable for a tried and true dev board that’s just been connector swapped to USB-C (and I’ll happily take it over dealing with Micro) but inexcusable for a new design.

My hope is Apple going USB-C only on all their charging bricks and now even C-C cables for the iPhone will eventually force Chinese OEMs to build standard compliant designs. Or deal with a 50% Amazon return rate for “broken no power won’t charge”.

4. Brusco_RF ◴[] No.41195560[source]
As someone who just picked micro USB over USBC for a development card, there is a significant price and footprint size difference between the two.
5. Findecanor ◴[] No.41195820[source]
For a device, USB-C requires two resistors that older USB ports don't.

Declaring yourself as a host/device is also a bit different: USB-C hardware can switch. Micro USB has a "On-the-go" (OTG) indicator pin to indicate host/device.

The USB PHY in RP2040 and the RP2350 is actually capable of being a USB host but the Micro USB port's OTG pin is not connected to anything.

replies(1): >>41196691 #
6. rvense ◴[] No.41196691{3}[source]
Hm, I've used mine as a USB host with an adapter? Not sure of the details, I suppose OTG is the online/runtime switching and I was just running as fixed host?