USB hosts hubs transceivers Forum Discussions

Hi All,

In our setup, we have a USB3 extender with local and remote units.  The Cypress Hub is on the Remote extender with two devices.  This is the setup

Host ....Local Extender ....Remote Extender..CYUSB3314-88LTXC Hub ----Seagate Backup Plus Portable Drive 1TB

                                                                                                                                            -----Aver VB342 (Isochronous) camera

When we cycle the power for the Remote or Local extender unit, we observe that sometimes the Hub does not enumerate. In these cases, the Host attempts three Warm Resets and when the Hub does not enumerate on the third attempt, the host gives up.

The above issue only happens when we have the Ghost Charging disabled on the Hub, but the issue is not seen when the Ghost Charging is enabled on the Hub.

The Lecroy Analyzer Trace collected shows that the Hub sends an NRDY packet but never sends back the ERDY. I have attached the Trace for your reference.

Can someone please let me know what is going on, and why the Hub goes into this lockup state?

Thanks,

Hi there,

I am currently using the CY7C65642 hub to connect to a Raspberry Pi CM4 host running the latest mainline kernel (Linux retropie 5.10.103-v7l+) in standalone boostrap mode (i.e with no MCU present). I've been able to get the chip working just fine and then Pi host is recognizing it via lsusb as a connected high speed device. The only problem here is when I disconnect my host directly from the USB-C port (i.e physically pull it out of the docking station). 

Does anyone know why this would be occuring? I've attached my relevant schematics here and setup, as well as the dmesg I get after the console is pulled out of the dock.

Interestingly enough, if I pull the USB-C adapter out the back of the dock and then back in, the device hub enumerates just fine (i.e I can do it mulitple times). A physical removal from the dock itself however results in this dmesg (note that if I pull it out quickly and then reinsert it within a very short time frame, the hub still seems to enumerate as a USB device). 

[ 162.044343] usb usb1-port1: disabled by hub (EMI?), re-enabling...
[ 162.044356] usb 1-1: USB disconnect, device number 5
[ 162.044364] usb 1-1.4: USB disconnect, device number 6
[ 163.554427] usb usb1-port1: Cannot enable. Maybe the USB cable is bad?

VBUS power is delivered to the hub when the CC lines negotiate a USB-C PD contract, the buck steps down the 5V and powers the hub. I currently believe based on my schematics I have the hub being self-powered (i.e the 0 ohm jumper R24 is not populated). 

Basic front dock PCB that has USB-C connector. VCC_5V is connected to SBU_DOCK1 which switches the TS3USB221A mux.  The left FFC connects the front dock PCB (containing the male USB-C plug to the rear board over an FFC). 

USB hub (CY7C65642) inside the dock:

Power circuitry (5v buck reg powering the hub) inside the dock:

USB 2.0 mux switch in console that switches to the docking USB lines to disconnect internal controller when docked: 

Is there anything in my schematic I should fix here/help to debug this issue?

Kind regards,
Benjamin