geekhack
geekhack Projects => Making Stuff Together! => Topic started by: Tom_Kazansky on Mon, 14 June 2021, 06:26:22
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Hello!
I have a plan of making an usb hub with integrated macro pad by using HS8836A chip.
I bought the chip https://www.aliexpress.com/item/32856126726.html (https://www.aliexpress.com/item/32856126726.html) and wired the board using the diagram in the product page.
(https://ae01.alicdn.com/kf/H2b1801c37de748d28c753530b9616148l.jpg)
the only difference is that I use USB-C instead of USB-MiniB.
after I have soldered necessary components for the hub and plug the board in, I got error "USB not recognized", I go to Device Manager to check the driver and it say "Unknown USB (Device Descriptor Request Failed)".
I wonder what went wrong, anyone know what could have caused this error? maybe I need some specific driver for this chip in Windows 10? :mad:
I used a multimeter to check for short-circuits but there is none so far.
thanks for reading.
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Can you share the PCB?
I guess you have a 2 layer board while ignoring impedance which is only fine/valid for short traces.
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You say you used USB-C instead of USB Mini. Did you add the necessary 5.1k resistors between CC1/CC2 and ground? Although, it should still work even without them when connected to USB 2.0.
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You say you used USB-C instead of USB Mini. Did you add the necessary 5.1k resistors between CC1/CC2 and ground? Although, it should still work even without them when connected to USB 2.0.
I did add the 5.1k resistors to CC lines.
I got the error "USB not recognized" when I plugged my board to USB 2.0 port,
there is no responses if I plug my board to USB 3.1 port.
I'm a bit skeptical about the V3.3, I did connect v3.3 (pin 14) to DCP (pin 12) with some capacitors around that line, is that right or did I misunderstand the diagram? :(
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i am not sure, but i do not think usb A to C cables have 3.3v so that may be part of the problem, when i checked last time most usb hub chips have their internal 3.3v regulators and exposes it for if you want to use an external one and decoupling and reading a bit about yours it looks to be the case with it too, this 3.3V does not need to be connected anywhere on the usb port, well as far as i know, i found 2 datasheets in Chinese, one toshiba transistor datasheet and a few projects using it, and only putting decoupling on the 3.3V and DCP.
although have you swapped D- and D+? if you did then there would be no communication in USB2.0 but i think USB3 is tolerant to them being swapped, or i may have understood that part wrong. it happens.
and yeah having schematics or board layout would allow to make better guesses, we are a bit blind right now
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Not recognized is almost always in my experience a sign that you swapped the two data lines like Yui said.
The Type C resistors are (there are two) "usually* only an issue if connecting to a native Type-C host device and port such as a Macbook, if it plugs into a Type-A you won't need it, just be sure it doesn't draw too much power and melt the connector, which if it draws power and data it should not be capable of doing due to power management. There's no sense in running 3.3v to that connector in order to use the resistors it's a 2.0 hub, it will not have any use for it other than to confuse the secondary system. If you're using it on the side that connects to the computer itself, you should NOT be connecting 3.3 to that as that power should come from the host system, not the secondary system.