USB hubs vs CircuitPython

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kevinjwalters
 
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USB hubs vs CircuitPython

Post by kevinjwalters »

I bought a cheap unpowered Anker USB hub recently and initial tests with three Circuit Playground Expresses/Bluefruits are not promising. I seem to only get one serial console and one CIRCUITPY drive showing up. A pair of cheap USB power meters tell me that the voltage and current (110mA, got some NeoPixels on) are reasonable. My monitor has a two port hub in it and the devices work ok in that.

Is there a particular hub feature that CircuitPython requires?

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mikeysklar
 
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Re: USB hubs vs CircuitPython

Post by mikeysklar »

Interesting finding.

Is the Anker USB hub you are using a USB v2 or v3?

I've had the best success with USB 2.0 powered hubs.

https://www.adafruit.com/product/961

Does it make any difference if you plug a lipo into the CPX Bluefruit while using the hub?

Do you have issues programming or bringing up a serial console when using Arduino code?

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kevinjwalters
 
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Re: USB hubs vs CircuitPython

Post by kevinjwalters »

It's a USB 3.0 hub. My desktop has a mix of ports and the Anker hub does seem to be viable if I plug it into a USB 2.0 host port and plug the CPX/CPB's in sequentially with a slight pause between each one.

My montiors are antiques and will be USB 2.0. I've ordered some cheap, no-brand USB 2.0 hubs and will do some more experimentation when they arrive, thanks.

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danhalbert
 
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Re: USB hubs vs CircuitPython

Post by danhalbert »

I had trouble with an inexpensive "Amazon Basics" 3.1 hub (USB-C). I have had much better luck with the aluminum-cased multi-function USB-C hubs that also have HDMI, Ethernet, etc. These are often advertised as port expanders for Macs (but I am using Linux).

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kevinjwalters
 
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Re: USB hubs vs CircuitPython

Post by kevinjwalters »

I got a cheap (sub 5 USD) one advertised as USB 2.0 and this seems to have done the trick even when used in a USB 3.0 A port . I plugged them in sequentially and I've got 4 CIRCUITPY drives and 4 COM ports. I'm keeping the power around the 110mA level per board (green pixels full on) as I imagine something bad will happen if I go much above that on this humble, unpowered hub.
Attachments
Low brand USB2.0 hub which seems ok for CircuitPython
Low brand USB2.0 hub which seems ok for CircuitPython
cheapo-usb2-hub-ok-circuitpython.jpg (7.3 KiB) Viewed 114 times

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mikeysklar
 
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Re: USB hubs vs CircuitPython

Post by mikeysklar »

Is the takeaway that reliable CircuitPython drive mounting and REPL console can currently be achieved via USB 2.0, but not so much with USB 3.x?

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danhalbert
 
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Re: USB hubs vs CircuitPython

Post by danhalbert »

mikeysklar wrote:Is the takeaway that reliable CircuitPython drive mounting and REPL console can currently be achieved via USB 2.0, but not so much with USB 3.x?
I would not say that. I use a USB-C port adapter that has 3 USB 3 "A" ports for all my CircuitPython debugging, and it's fine. It was the cheap USB 3.1 hub that had trouble.

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kevinjwalters
 
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Re: USB hubs vs CircuitPython

Post by kevinjwalters »

The picture I posted before is a bit misleading with the blue plastic on the four USB ports. My one looks like this one.
cheapo-usb2-hub-ok-circuitpython-ports-black-plastic.jpg
cheapo-usb2-hub-ok-circuitpython-ports-black-plastic.jpg (13.97 KiB) Viewed 80 times
I'll try both hubs with my laptop at some point.

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