Possible for stusb1602 SNK to negotiate higher PD voltages without SPI?

[CMill.4]

I'm building a sink only type PD device using a SAMD21G18A and the stusb1602, because the stusb4500 was not available so we changed our design. I have i2c communication with the device, and can read/write to the NVM (although I'm not sure I have the memory layout correct). I do not have SPI routed to the MCU. Is it still possible to negotiate over the CC lines with a 20V capable source, without SPI? I'd like the stusb1602 to behave as much like the stusb4500 as possible.

[NBALL]

Hello

stusb4500 is an autonomous USB PD controller which is able to negociate by itself a contract, based on PDO stored in its NVM.

stusb1602 is BMC driver which mandates STM32 MCU partner to make a PD contract. SPI is mandatory and stack is actually ported on stm32F072-stm32L4R5-stm32F446-stm32G474 and will be available soon on stm32H723 (visit stusb1602 page for FW package selection vs MCU).

May I know your project schedule please ?

Best regards

[CMill.4]

We would have used the stusb4500 if it were available for purchase. Our schedule is ASAP. We selected the 1602 because the 4500 was impossible to get, and the documentation is not immediately clear that SPI is required for our use case. The datasheet hardly mentions SPI, let alone demonstrate how to use it and when it's required. We do not have SPI on this board.

[NBALL]

I do apologize if it was not clear enough but datasheet mentions that stusb1602 is TX/RX line driver & BMC transceiver, on 1st page.

BMC interface block diagrams shows that SPI is the 'data path' for USB power delivery messages. (paragraph 3.2).

Best regards