HD3SS3220: Set DISABLE _TERM and DISABLE _UFP_ ACCESSORY in the state other than "Not attached"

Saito:

   I will update soon (tomorrow) once I get answer.

Regards,

Brian

Hi Saito,

1. HD3SS3220 will attached per table 4.5 in the datasheet as a audio or debug accessory which is seen differently than a Attached.SNK state. 

2. It is recommended to detach the UFP when making functional changes to HD3SS3220 this is done by either DISABLE_TERM or physical dis-attachment.

3. Yes, DISABLE_TERM can be set when in other states and will cause the USB-C link to be "Unattached". This would be the same for ENn_CC. 

Hello Malik,

Thanks for your comments. Regarding #1 inquiry, Could you allow me to clarify it in more detail, please?

According to USB Type-C spec(Figure 4-14), Sink device (UFP) with Accessory support shall transition to Unattached.Accessory state and return to Unattached.SNK. HD3SS3220 is UFP mode and "UFP accessory support", if HD3SS3220 (UFP) is staying in Unattached.Accessory state and other UFP device is attached in this condition, can we consider HD3SS3220 ignore this event?

I believe so because attached device is Not accessory, but, I’d like to check it.

Best regards,

Miyazaki

Hi,

If the attached device is UFP only and no accessory mode that means that there could be a Rd on both ends of the CC line. I expect HD3SS3220 to not see any toggling from attached UFP.  

Miyazaki:

    Which Type-c spec version of figure 4-14? 3220 only support Type-c spec 1.1.

Regards,

Brian

Hi Brian, Malik,

Thanks for your comments.

Although we set HD3SS3220 to just UFP mode and verified CC terminals, it seems, HD3SS3220 is working like DRP(CC toggle). TUSB322 also has same behavior. we tried to checked the reason and noticed UFP_accessory_support is enabled by Default. However, we are not sure how HD3SS3220 is working under this condition when other UFP device will be attached.

Best regards,

Miyazaki

Hello,

Can we have your Expert's comments on this, please?

Best regards,

Miyazaki