Cermetek Microelectronics, Inc Page 11 of 42
Document NO. 607-00xx Revision A (12/13)
CH232BGN modules operate in either Transparent Transmission Mode or Configuration Mode.
Configuration is accomplished through AT+ commands.
1.4.1. Transparent Transmission Mode
The CH232BGN supports transparent data transmission through its serial interface. Once power is
applied, the CH232BGN connects automatically to the wireless network with minimal configuration
changes.
Notes: Transparent transmission requires flow control to be active to prevent data transfer errors.
Enable hardware flow control (RTS/CTS) on the UART port to prevent buffer overflow.
1.4.2. Configuration Mode
In configuration mode, the user can set CH232BGN configuration. The user can switch from
transparent transmission to the configuration mode using the AT+ commands described in Chapter 4.
1.4.3. Multi-TCP Link Connection
When the CH232BGN module is configured as TCP Server, it supports Multiple TCP connections. A
maximum of 32 TCP clients can connect to one CH232BGN module. Figure 9 below illustrates
Multiple TCP Connections
Upstream: Data from each TCP connection or client is transmitted to the serial port in sequence.
Downstream: The CH232BGN duplicates and broadcasts data from the serial port to every TCP
connection or client.
Figure 9: Data Flow for Multiple TCP Connections
