TUSB8041A: USB HUB TUSB8041A stops working issue.

Hi Zeros:

        Where is USB_VBUS connected to? It should be around 0.5v.

       Don't know why I can't search in schematic file, can you send a new one I can search ?

Regards

Brian

Hi Brian,

Attached is updated schematic.

Zeros:

   I didn't see issue in schematic  which could cause crystal stop working.

   From this waveform , crystal never start working. Is crystal far from HUB device? or any  hub soldering issue for ground pad?

Regards

Brian

Hi Brian,

The etch length from crystal to HUB is about 356mils and we can measure crystal working at 24Mhz as below picture,btw,we found the HUB can normal working when re-assert reset signal.

Zeros:

  Is that Windows system turn on low power state ( U3) ? It may cause crystal to stop.

Regards

Brian

Hi Brian,

Do you know how to check whether a OS(Windows server 2002) is entring U3 state? btw,We use same OS for another system and didn't find any issues.

HI Brian, we checked the USB HUB crystal also stop at BIOS menu, it didn't related to OS behavior (checked linux and windows also duplicated).

and we tried to re heat chip but still fail, please help to comments if any.

Thanks

Sinden:

   let me check with designer what any other reason could cause crystal stop working and update on next Monday.

Regards

Brian

Hi Brian, do you have any update?

BTW, the board is designed based on TUSB8041RGCR, and change to TUSB8041ARGCR, 

if it need any desgin change for that?

Hi Brian,

update 1 items, we tried to remove the EEPROM, and the HUB can works normal, if any EEPROM data need modify for change from TUSB8041 to TUSB8041A?

Hi Brian, so it will cause the HUB stop working?

and could you help to provide the default TUSB8041A EEPROM data for try?

Thanks

Hi Sinden:

   Do you plan to change any setting? default setting itself should work. I can send EERPOM file you need to change anything.

Regards

Brian

Hi Brian,

Default setting TUSB8041A EEPROM File is fine, please help to provide,

BTW if "Removing EEPROM" is equivalent to loading default EEPROM"

Thanks

Sinden:

   "Removing EEPROM" is equivalent to loading default EEPROM. If you need to change anything, then you need to external EEPROM.

Regards

Brian

Hi Brian, ok but still need you help to provide the TUSB8041A default ROM for try, and please also provide the EEPROM related tool as well.

BTW, the ROM setting will cause the "Stop working " ?

Thanks

Sinden:

           Please accept my friendship request and I can send EEPROM tool to you.

          By the way, what did you change your original EEPROM file?

Regards

Brian

Hi Brian,

I've accepted the request. please help to provide.

and we didn't change any EEPROM

Hi Brian 

We would like to know about Bit 2 of register 0A more detail information,could please provide a detailed explanation of the DSPORT ECR(Does it mean 'Error Correction Register'?) enable mechanism and its operation and Is the abnormal operation of TUSB8041 related to this bit?

Thanks.

Zeros:

ECR means Engineering Change Request.

For this ECR, if it was disabled, downstream port will stop reporting port status, so I don't think it will cause the abnormal operation.

Please check bit 5 of 0x05 to see if U1/U2 is disabled or not.

Regards

Brian

Zeros:

    Did you try TI EEPROM tool and find any register related? 

Regards

Brian

Hi Brian,

Yes, but we encountered another problem when loading the indicated driver for EEPROM tool, which caused all of the HUBs to stop working, and then the mouse and keyboard shut down,So we are looking for a PCIe to USB card to resume mouse and keyboard functions.

Hi Zeros:

    You are right, EEPROM tool driver will disable all USB ports on the same root hub and you need  PCIe to USB card to control mouse and keyboard.

After exit from EERPOM tool, you need to reboot the system to make hub work as normal.

   Please keep update if you make progress

Regards

Brian

Hi Zeros:

    Any progress to use  EERPOM tool?

Regards

Brian