The end device is a compound USB device (hub + 1 or more embedded devices). I would like to set the hub descriptor to indicate the required power. I'm assuming this would be done on the HS hub and not the SS hub.
Is this possible?
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The end device is a compound USB device (hub + 1 or more embedded devices). I would like to set the hub descriptor to indicate the required power. I'm assuming this would be done on the HS hub and not the SS hub.
Is this possible?
Hello:
per USB specification device descriptors must report the device configuration (bus-powered vs. self-powered) and max VBus power consumption.
In the case of the TUSB8043A, this data is fixed reporting the device as a self-powered USB Hub with 0mA bMaxPower.
Functionally you can configure the TUSB8043A as bus-powered, and it will have no issues; however it will not pass USB compliance tests since the descriptors will always report a self-powered configuration..
Regards
Brian