Datasheet CH9121 (Nanjing Qinheng Microelectronics) - 7

CH9121 Datasheet https://wch-ic.com Network cable When the network cable is disconnected, you can configure CH9121 to actively close disconnection the TCP connection internally or take no action. processing The RX packet length range is 1 to 1024. When the CH9121 serial port receives data RX packet length of the set length, the CH9121 will immediately package the serial port data and transmit it out through the network. The timeout setting range is 0 to 200, and the unit time is approximately 5 milliseconds. For example, if the timeout value is set to 1, a serial port timeout will occur when the data length of the serial port receive buffer does not reach the RX package length and the serial port does not receive new data within 5ms. RX packet timeout When the serial port timeout occurs, CH9121 will transmit the data received by the serial port through the network. When the timeout is set to 0, the internal hardware timeout (no new data is received for more than 4 data times) mechanism is enabled, which is suitable for occasions with high real-time requirements and large-volume data transmission and reception. Network connection The data received by the serial port before the TCP connection is established can be operation cleared (discarded) or retained when TCP is established.
5.4 Default Configuration
When CH9121 leaves the factory, port 2 is closed by default and port 1 works in TCPCLIENT mode by default. The default network parameters are shown in the table below. Table 5-3 Default configuration Default Configuration Description Device IP 192.168.1.200 Subnet mask 255.255.255.0 Default Gateway 192.168.1.1 Local port 2000 Destination IP 192.168.1.100 Destination port 1000 Serial port negotiation Off, do not allow entering serial port configuration mode configuration through serial port handshake Baud rate 9600 Data bit 8 Stop bit 1 Check None Network cable disconnection Actively close the TCP connection processing RX packet length 1024 RX packet timeout 0 Network connection Do not clear the serial port buffer operation V2.5 7 Document Outline 1. Overview 2. Features 3. Pinouts 4. Pin Definitions 5. Function Parameter Descriptions 5.1 Overview 5.2 Basic Parameters 5.3 Port Parameter 5.4 Default Configuration 6. Function Descriptions 6.1 UART 6.1.1 Serial Baud Rate 6.2 Other Hardware 7. Parameters 7.1 Absolute Maximum Value 7.2 Electrical Parameters 7.3 Power Consumption 7.4 AC Electrical Characteristics and Timing 8. Package Information 8.1 TSSOP20 8.2 LQFP64M 9. Applications 9.1 CH9121T Reference Circuit 9.2 CH9121A Reference Circuit