Basic USB-C Source

Overview

This example demonstrates how to create a USB-C Power Delivery application using the USB-C subsystem. The application implements a USB-C Source device.

After a USB-C Sink device is plugged into the USB-C Source device, it negotiates with the Source device to provide 5V at 100mA, 9V at 100mA, or 15V at 100mA and the Requested Data Object (RDO) provided by the Source is displayed.

Requirements

The TCPC device used by the sample is specified in the devicetree node that’s compatible with usb-c-connector. The sample has been tested on stm32g081b_eval. An overlay file is provided.

Building and Running

Build and flash as follows, changing stm32g081b_eval for your board:

west build -b stm32g081b_eval samples/subsys/usb_c/source
west flash

Connect a sink device and see console output:

Sample Output

PRL_TX_SUSPEND
PRL_HR_SUSPEND
PE_SUSPEND
UnattachedWait.SRC
Unattached.SRC
AttachWait.SRC
Attached.SRC
PE_SRC_Startup
PRL_INIT
PRL_HR_Wait_for_Request
PRL_Tx_PHY_Layer_Reset
PRL_Tx_Wait_for_Message_Request
PE_SRC_Send_Capabilities
PRL_Tx_Wait_for_PHY_response
PRL_Tx_Wait_for_Message_Request
PE_SRC_Discover
PE_SRC_Send_Capabilities
PRL_Tx_Wait_for_PHY_response
RECV 1042/1
   [0]1300280a
PRL_Tx_Wait_for_Message_Request
PE_SRC_Negotiate_Capability
PE_SRC_Transition_Supply
PRL_Tx_Wait_for_PHY_response
RECV 0441/0
PRL_Tx_Wait_for_Message_Request
PE_SRC_Ready
PRL_Tx_Wait_for_PHY_response
RECV 0641/0
PRL_Tx_Wait_for_Message_Request
REQUEST RDO: 1300280a
 Object Position:         1
 Giveback:                0
 Capability Mismatch:     0
 USB Comm Capable:        1
 No USB Suspend:          1
 Unchunk Ext MSG Support: 0
 Operating Current:       100 mA
 Min Operating Current:   100 mA