## UART

It can be learned from the data manual that the ssd20x has four serial ports, including three ordinary UARTS and one fuart with flow control function:

# vi arch/arm/boot/dts/infinity2m-doublenet.dtsi

The serial port configuration is as follows（infinity2m-doublenet.dtsi）：

# vi infinity2m-doublenet.dtsi
    aliases {
console = &uart0;
serial0 = &uart0;
serial1 = &uart1;
serial2 = &fuart;
serial3 = &uart2;
};

Refer to the following：

UART2 is not enabled in the DTS of the kernel. The default mode is GPIO. If necessary, please refer to:http://doc.industio.com/api/ido-sbc2d06/edit/

Test

The test program can be obtained from the network disk. Serve as TX and Rx ports of the development board respectively.The data sent by the sending end is 0-255, and the receiving end prints out the sent data. The received and sent data are hexadecimal. If no data is received, the timeout information will be printed.
UART0, UART1 and UART2 are TTL levels.

1. Copy the compiled executable file to the development board

2. Execute the receiving executable

./rs232_test_fuart_rx  /dev/ttyS1 115200 8 1 N ./uart1.log 2M 

3. Execute the sending executable

./rs232_test_fuart_tx  /dev/ttyS1 115200 8 1 N ./uart1.log 2M