TUSB4020BI: TUSB4020b trouble shooting

Terry Wu

Expert 1680 points

Part Number: TUSB4020BI
Other Parts Discussed in Thread: AM3352

Hello every experters,

OS: Wince 6.0

SoC: AM3352

Now the Hub downstream port could identify Keyboard/Mouse or other USB devices.

VDD1.1 and VDD33 is no problem . 24MHz X-tal also work fine . Grstz pin place 1uF , power on reset great than 3mS .

Is there other check points need to care ?

Does Wince need USB hub driver ? <= I don't make sure .

Schematic as attach file.

Pls give your experience sharing and many thanks so much ~

0 Elias Villegas M. over 8 years ago

Hello,
Yes, your WIN CE requires USB driver support.
Are you having an issue? Can you elaborate more?
Regards

0 Terry Wu over 8 years ago in reply to Elias Villegas M.

Expert 1680 points

Hello Elias,

May I know the pin "SMBUSz"

We keep this pin "NC" and pull down this pin .Hub can't work.

I pull up this pin the Hub could work,why ?

No EEPROM populated.

No SoC's i2c bus controll Hub now.

Many thanks !

0 Elias Villegas M. over 8 years ago in reply to Terry Wu

Hello,

When you pull SMBUSz down you are selecting SMbus mode, in this mode you have to clear the CFG_ACTIVE bit in order to stablish upstream connection.

You have to leave this pin NC or pulled-high.

See section 8.5.3 in the datasheet.

0 Terry Wu over 8 years ago in reply to Elias Villegas M.

Expert 1680 points

Hello,
I got it and many thanks ~

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