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STUSB1602 firmware problem.

Associate II


During testing with the STUSB1602, I encountered strange behavior when using the DRP-mode. Connecting a USB power bank in this mode does not result in a successful connection. Only after pressing the engage-button on a Powerbank, the connection is made and the PD-negotiations are started about the best sink to draw power from the Powerbank.

After carefully debugging, I saw that the CAD-state always goes to source when connecting in DRP-mode. This is CAD-state enumeration 9. This enumeration is state USBPD_CAD_STATE_SWITCH_TO_SRC in the STUSB1602 firmware.

However, this enum 9 is USBPD_CAD_STATE_SWITCH_TO_SNK in the STM32G firmware. This firmware works correct.

If I change the enums to fit the enums of the STM32G firmware (9 = USBPD_CAD_STATE_SWITCH_TO_SNK; 10 = USBPD_CAD_STATE_SWITCH_TO_SRC) all works 100%.

Could this be an firmware error ?