Enable power out to debug accessory using CYPD5225_notebook_tbt project

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KiLe_4629881
Level 3
Level 3
25 sign-ins 10 replies posted 10 questions asked

Hi, 

I have a debug accessory I have created that pulls both CC1 and CC2 to ground through 5.1k resistors.

This is correctly recognized as a debug accessory by the PD controller and I can configure the mux to my specifications to send debug signals out. However I would also like to supply 5V on VBUS (enable psrc) to the debug accessory so it can be powered from the host at the same time. Looking through the source to the project I am not sure how to do this, as I think this is done by the DPM. 

Is this possible?

Thanks for your help

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1 Solution
Sananya_14
Moderator
Moderator
Moderator
750 replies posted 500 replies posted 250 solutions authored

Hi,

To turn on the source path , please try calling the psrc_enable() function which turns on the VBUS provider FETs after checking for debug accessory connection in the APP_EVT_CONNECT event in app_event_handler().

Best Regards,
Sananya

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5 Replies
Sananya_14
Moderator
Moderator
Moderator
750 replies posted 500 replies posted 250 solutions authored

Hi,

If the connected device is recognized as a debug accessory and it enters debug accessory mode, I dont think PD communication is enabled in the CCG5 firmware since it is considered optional as per the Type-C Spec. Based on the CC pin terminations, I think CCG5 would enable VBUS if the connected device is a sink, when it's role is set to source.

Could you please check the PD logs and let me know if there is any communication? Please also let me know if disabling the debug accessory mode in the configuration allows VBUS to be sourced?

Best Regards,
Sananya

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KiLe_4629881
Level 3
Level 3
25 sign-ins 10 replies posted 10 questions asked

Yes the device is entering debug accessory mode without PD communication (just resistor termination). However I don't see the ccg5 enabling vbus when I measure with a multimeter: 
[58640.766147 =====Port 0======]
[58640.768565 PD_STATUS NoContract DataRole:DFP PowerRole:Source Vconn:Dis]
[58640.770540 TYPE_C_STATUS : Connected CC1 Debug NoRa 3A]
[58640.773200 RDO : Current:0mA MaxCurrent0mA 0x00000000]
[58640.775834 PDO : MaxCurrent:0mA Voltage0mA 0x00000000]
[58640.777876 TYPE_C_VOLTAGE : 0mV]

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Sananya_14
Moderator
Moderator
Moderator
750 replies posted 500 replies posted 250 solutions authored

Hi,

Can you please provide your schematics for our reference if its not confidential? Please let us know if CCG5 is providing VBUS if a PD sink (Rd and Ra terminations) is connected to the port instead.

Best Regards,

Sananya

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KiLe_4629881
Level 3
Level 3
25 sign-ins 10 replies posted 10 questions asked

Hi Sananya, 

Yes CCG5 can provide 5V out to a device using VBUS_P_CTRL_Px pin when a device is attached to one CC pin using Rd=5.1k. 

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Sananya_14
Moderator
Moderator
Moderator
750 replies posted 500 replies posted 250 solutions authored

Hi,

To turn on the source path , please try calling the psrc_enable() function which turns on the VBUS provider FETs after checking for debug accessory connection in the APP_EVT_CONNECT event in app_event_handler().

Best Regards,
Sananya

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