Middleware stack complies with USB Type-C and Power Delivery
Based on STMicroelectronics’ microcontrollers, the free STM32 USB-C and PD Middleware Stack is compliant with USB Type-C 1.2 and USB Power Delivery 2.0 specifications. It enables customers to deploy the technology in end-products, exploiting the feature set of the ARM Cortex-M based microcontrollers.
The X-CUBE-USB-PD firmware stack, initially based on the STM32F0 entry level Cortex-M0 processor, allows designers to upgrade USB legacy devices as USB-C with Power Delivery technology provides a reversible connector. It can carry data (including video or proprietary protocols), and up to 100W of power to supply or charge equipment connected to the USB port.
Cost and footprint savings can be made using the STM32 with the stack, as only a simple analogue front end, comprising a few passive components, is required, says the company, as it exploits STM32 embedded features such as comparators, ADCs, timers, and direct memory access.
The stack can support up to two USB-C ports (provider, consumer, or dual role), vendor-defined messages are handled to identify device or cable ID or to manage alternate mode commands.
The software library provided in the X-CUBE-USB-PD software expansion is in line with STM32Cube APIs (hardware abstraction layer or HAL), to switch across different STM32 series.
The company’s STM32 Nucleo Pack is also available. It includes a Nucleo-F072RB board, a USB-C and PD expansion board, and a USB Type-C cable. The expansion board features two dual-role power USB Type-C ports with a discrete analogue front end.