STMicroelectronics has released software to make its STM32G0 32bit Cortex-M0+ microcontroller into a UCSI ‘platform policy manager’ (PPM) to manage USB Type-C connectors – in particular for its STM32MP135F-DK development board.

ST X-CUBE-UCSI expansion package
UCSI is the USB Type-C connector system software interface, controlled by a specification from the USB Implementers Forum.

The software, ‘X-CUBE-UCSI expansion package’, consists of libraries, drivers, sources, APIs and an application for the STM32G071. It “helps developers to build a USB PD dual-role power [DRP] application as well as to support alternate-mode commands”, according to ST.

The development board above has an STM32MP135 MPU application processor acting as UCSI ‘OS policy manager’ (OPM) to interface with the PPM-enables MCU above, via I2C with the UCSI interface.

 

The software lets the MCU connect to the MPU and exchange information with the operating system using the UCSI protocol, while controlling the USB-C attachment and PD protocol.

It also allows firmware programming of the MCU via the main processor.

“The main processor uses the UCSI driver, from Microsoft or available in the Linux community, and associated commands to exchange data with the PD controller,” said ST. “This extends interoperability between USB-C devices to support the latest use cases.”

The result is compliant with USB Type-C 1.3, USB power delivery 3.0 and UCSI 1.2.

X-CUBE-UCSI, which is expanded by the new package, is a UCSI-certified hardware-firmware combination.