4 Replies Latest reply on Apr 16, 2018 5:51 PM by dagac_3259706

    CY7C65632-TQFP48 downstream power control



      We are using the CY7C65632-TQFP48 (4-port hub), In this hub data sheet given as each down stream port power controlled by PWR#(port power pins) When the hub is configured, the ports are not driven and the host may power the ports by sending a SetPortPower command for each port. But default hub is configured and 4-port are working and how to send the SetPortPower command to hub to control the down stream ports (use set port power command is given in datasheet).








      Sandeep V

        • 1. Re: CY7C65632-TQFP48 downstream power control



          Are you using custom driver for hub?



          • 2. Re: CY7C65632-TQFP48 downstream power control


            I am struggling with the same issue - the documentation is crap! it does not say anything about where the command SetPortPower should be sent and what is the code for that command.


            Did you ever solve that problem?

            • 3. Re: CY7C65632-TQFP48 downstream power control

              Hi Sandeep,


              The context you mentioned in datasheet are facing to the person who develops host driver, i.e., Intel or Microsoft who provide the driver on PC.

              Consequently, if you simply use HUB to make a hardware designm, you don't need to care about these things.

              Just follow the hardware design guide to make your schematic and PCB layout.

              • 4. Re: CY7C65632-TQFP48 downstream power control

                Hi yyca,

                I wonder if Cypress has considered the fact that Microsoft is not the only developer of drivers. We are also trying to design an OEM system and we need to control the power delivered to each downstream port. The issue is not limited to the HUB itself. our platform is Linux and the OS USB interface is very limited. The OS is not able to consistently map all the USB hub levels that are connected to its root hub, this makes it difficult to use the control interface to send commands to a particular hub. (granted hubs are enumerated in the same order on power up / reset of the OS but once any device is plugged or disconnected the order is no longer consistent). To add insult to injury the documentation of the HUB chips is very tight lipped about how the hubs port power must be controlled. As result we will probably have to go elsewhere for a HUB chip.