USR-WIFI232-B2 Hardware Manual
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Jinan USR IOT Technology Limited 7 / 9
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2.4.2.Ethernet Interface without Transformer
For this application, Ethernet interface will work as internal data interface. Ethernet PHY-to-PHY connection
will use AC coupled connection. This is a space and cost optimized solution.The design should pay attention
to the driving type of PHY chip. PHY chip inside B2 module is current driven, so two side PHY chip are current
drivers can be directly connected.Otherwise, transformer can't be saved. Circuit diagram as follows:
Note: VCC signal at reference design shall base on user board PHY chipset voltage level, such as 2.5V
power supply for general Ethernet PHY chipset.
USR-WIFI232-B2 Ethernet interface default is for the application with transformer connection. If user need
PHY-PHY directly connection, please refer to above diagram and use follows AT commands
：
AT + VEW = enable < CR > to open Ethernet WAN port (Can restore to default settings by reload)
or AT + FVEW = enable < CR > open Ethernet WAN port (not affected by Reload).
Remark:
1. Only when Ethernet used as WAN, this command is needed. Module default is LAN port.
2. After this command, ensure module WAN IP and LAN IP in different network segment. (Modify the LAN IP
