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Problem with the speed of GL850A USB Hub

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Tohu

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Hello to all,
Did somebody have experience with this chip? This is a USB 2.0 HUB the problem is that the chip work only like a USB 1.0 Hub, for some reason can't be switched to Full speed mode. The PCB is made according app note and USB 2.0 specification, I compare the circuit diagram with a working USB 2.0 hub with this chip, and I can' see any different, except one. The chip in this hub is 68 pin packages I am using a 48 pin. From each data pin thy have a 15 k to GND /I have too this resistor/ and 330 Ohm to pin on the side of data pin, marked as NC in data sheet.
Thanks in advance.
 

gl850a driver

Tohu said:
Hello to all,
Did somebody have experience with this chip? This is a USB 2.0 HUB the problem is that the chip work only like a USB 1.0 Hub, for some reason can't be switched to Full speed mode. The PCB is made according app note and USB 2.0 specification, I compare the circuit diagram with a working USB 2.0 hub with this chip, and I can' see any different, except one. The chip in this hub is 68 pin packages I am using a 48 pin. From each data pin thy have a 15 k to GND /I have too this resistor/ and 330 Ohm to pin on the side of data pin, marked as NC in data sheet.
Thanks in advance.

Maybe the host you are using is only supporting USB 1.1. Please check it out!
 

usb hub circuit diagram

I know this is an old post, but maybe this will answer some questions.

Download and run the program USBVIEW. It will display the configuration parameters for your USB HUB. You will find out that the ROM in this HUB has probably been programmed wrong.

look at the value

bcdUSB : 0x110 // This hub is programmed to be USB 1.1
bddUSB : 0x200 // This Hub is programmed to be USB 2.0

It doesn't matter what the hardware is... The Hub is telling windows it's only 1.1. compliant. Mine also says it was made by Atmel Corpororation... Thats probably wrong too.
 

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