Clarification on communication transport between STM32U585 and QRB2210 on UNO Q

[philippe86220]

Hello,
Clarification:

The documentation indicates that the Bridge (RPC layer) can operate over multiple physical transports.
The hardware block diagram of the Arduino UNO Q shows two possible inter-processor connections between the STM32U585 (MCU) and the QRB2210 (MPU):

• LPUART1
• SPI3

Could you please confirm which physical transport is used by the current public firmware, and whether the second one (SPI3) is reserved for future high-speed data exchange?

Thank you.

[pillo79]

That is entirely correct. RPC currently works over LPUART1, but SPI is also connected, and the ultimate goal is to use the latter for long burst of data to avoid hogging the serial interface.