Cermetek Microelectronics, Inc Page 9 of 42
Document NO. 607-00xx Revision A (12/13)
nLink
is an active low output that indicates a WiFi link is established. There is an internal
4.7K Ohm pull-up resister on this signal.
nReload
is an active low input. When activated for more than three (3) seconds, it causes the
module to reset the internal configuration to factory defaults. A 4.7K pull up resistor must be
installed at the nReload pin.
UART_TXD/RXD
signals provide the pathway for serial data to and from the UART; transmit
data (TXD) and received data (RXD). These signals include a 1L ohm pull-up resistor.
1.3.2. 10/100M Ethernet Interface
The CH232BGN provides one 10/100M Ethernet PHY layer interface for data transfer or user
configuration. The User circuit board must include an Ethernet transformer and RJ-45 connector. This
creates a standard 10/100M Ethernet physical layer connection. See the reference design below:
Figure 6: Ethernet Reference Design with Transformer
1.3.3. UART Interface
UART interface is the serial data transmission interface primarily used for the CH232BGN. The User
can add RS-232 drivers on their board to convert the signals to RS-232 voltage levels for
communications with outside equipment or sensors. CH232BGN modules UART interface include 4
signals: Transmit Data (TXD), Received Data (RXD), Request to Send (RTS), and Clear to Send
(CTS). The hardware reference design with RS-232 chipset as following:
