How to implement USB DPM, prevent hard reset

[Nv7]

I tried following STM32 AN5418 but the EvaluateSinkCapabilities method is not getting called. I added debug prints everywhere in the code and here is what I am receiving:

1. VBusInit (this always happens)

2. DPM notification 104 (Stack init)

3. Cable detection

4. Unimplemented SetDataInfo 8 (USBPD_CORE_EXTENDED_CAPA)

5. SetDataInfo 6 (USBPD_CORE_DATATYPE_RCV_REQ_PDO

- I haven't implemented anything in this, but I had it print out what it received and it looked good (e.g. 5V 3A 9V 3A 20V 5A etc.)

6. Notification: 30 (USBPD_NOTIFY_HARDRESET_RX)

7. Hard reset callback

8. Device turns off, turns on a few seconds later and goes through this same loop

What do I need to implement to get this working? Is this just because all of my methods are unimplemented besides EvaluateSinkCapabilities and one of the cases in GetDataInfo? At what point/do I call USBPD_DPM_RequestMessageRequest?

[FBL]

Hi @Nv7 

Would you describe your working environment? Would you attach your project? 

USBPD_DPM_RequestMessageRequestfunction is used to send a power request to the source device based on the selected Source PDO and the prepared RDO. Check this example.