Microchip Technology EVB-USB7056, Руководство пользователя

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EVB-USB7056 Evaluation Board User’s Guide
DS50002887A-page 14  2019 Microchip Technology Inc.
ware image. This mode of operation should only be used for debugging or
for loading a new firmware image to the SPI Flash. (The shunt should be
removed right before loading the new firmware image to the SPI Flash.)
2.3.4 Host Connection
A USB2.0 or USB3.1 host must be connected to the upstream Type-C port J2.
If connecting the hub to a Type-A host port, use a USB Type-A-to-Type-C cable. Note
that advanced functionality enabled through USB PD cannot function when using a
Type-A-to-Type-C adapter cable.
If connecting the hub to a Type-C host port, use a USB-IF-certified cable that supports
USB3.1 data protocol to ensure the highest functionality is supported by the cable. If
the host supported Power Delivery and requests power from the EVB-USB7056, the
negotiated voltage can be observed by monitoring the VBUS diode voltmeter on
D25-D28. If the host also supports DisplayPort Alternate Mode, then a display may
optionally connected to the EVB-USB7056 via a DisplayPort cable connected to J31.
Note: Charge-only Type-C cables with missing USB data wires (either missing
USB3.1 wires only or missing both USB2 and USB3.1 wires) do exist.
Always ensure to use USB-IF certified, known good cables when testing with
the EVB-USB7056.
2.3.5 Downstream Port Connections
Once host connection is established on the upstream host port, devices may be con -
nected to the downstream ports to begin operating with the USB host. The downstream
port VBUS LEDs may be used to verify that power is properly applied to the down -
stream ports. Failure to illuminate indicates either a host connection failure (VBUS is
enabled by the hub only when a command is received from the USB host) or a possible
overcurrent condition on the downstream port.