TUSB216I: any register can check the device status

Hi Jim,

1. I saw there are 4 registers in DS as below but looks no any register can be used.
Can you explain what you mean by "no any register can be used"?  Why can't they be used?

2. And when RSTN is low, could customer reading information through I2C?
The customer might be able to read through I2C during reset, but I wouldn't recommend it.  The registers may change after de-asserting completing the toggle.  What is the reason the customer wants to do this? 

3. Is the device I2C address 0x2C?
Yes, the 7-bit I2C device address is 0x2C.

If there are issues changing the registers.  Maybe section 7.4.6 of the datasheet is helpful:

" It is advised to set CFG_ACTIVE bit before changing values. This halts the FSM, and reset it after all changes are made. This ensure proper startup into high-speed mode."

Regards,

Nicholaus

Hi Malone,

Sorry for confusing.

for 1. I mean customer would like to check whether the device is work normally after reset through I2C, so they are looking for any information can identify the device is work from our register.

Hi Jim,

You can check all registers, since there is only 4 of them.  Read back the values of 0x01, 0x03, 0x0E, and 0x25 to make sure they are set to their default values.

Alternatively, they can see the effects of the redriver on the USB 2.0 signal by using an oscilloscope and changing the signal conditioning settings.

Regards,

Nicholaus

Hi Jim,

Can you tell me what CM/OEM this is?

Regards,

Nicholaus

Hi Malone,

CM is Inventec and so far no specific OEM, this is customer internal POC and will propose to China customer like Baidu/Tencent/Bytedance.

BTW, one more question, how to enter i2C mode?

Hi Jim,

Thanks for the explanation.  

To enter I2C mode the TUSB216I should powerup with the SCL and SDA lines pulled high with I2C-standard pullups.  Our EVM uses 4.7K pullup resistors.

"This controller is enabled after SCL and SDA pins are sampled high shortly after return from shutdown. In this mode, the CSR can be accessed by I2C read/write transaction to 7-bit slave address 0x2C" - Section 7.4.6 of datasheet.

Regards,

Nicholaus