The USB2 port 0 is used as the default port to present the module as a USB device to host systems. This mode is also used for updating the module firmware by reading the code from a connected storage device.

The signals for the USB2 port 0 are on connector J6 (pins 6 and 8 for USB2_0_DP and USB2_0_DN). The USB device connector is a micro connector. USB2 requires a common mode choke with ESD protection on the USB2_0_DP and USB2_0_DN signals. Add ESD protection diodes, and EMI dampening ferrite or a specially designed EMI filter capacitor to USB +VBUS. It is also good design practice to put a PTC fuse in series with +VBUS.

Attach the connector +VBUS pin to the +VBUS signal on the module to wake the module when the USB is inserted. The +VBUS also needs to be connected for the DnX protocol to work. The USB2_ID_PMIC pin can be left unconnected if the USB2 port 0 is not going to be used in host mode.

 

 

USB2 port 0 Signals

Signal

Module Connector.Pin

Pin Direction

Use

USB2_0_DP

J6.6

Bidirectional

USB 2.0 port 0 data positive

USB2_0_DN

J6.8

Bidirectional

USB 2.0 port 0 data negative

USB2_ID_PMIC

J6.20

Output

Low resistance indicates a USB OTG connection.

+VBUS

J6.99

Output

USB +VBUS power, also wake source for the module

Note: For +VBUS, less than 1 kΩ measured by the module indicates a USB OTG connection. Do not add pull-ups. Leave floating if not connected.

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