Using virtual serial port to debug serial port in keil MDK

Read a lot of articles , It's all very simple （ It's also very simple ：)）. Give a more detailed tutorial .

1.       utilize VSPD take PC Connect the two virtual serial ports on the . As shown in the picture, I will COM2 and COM3 Connect . Click on Addr pair.

2.       You can see Virtual ports Connect the two virtual serial ports together .

3. The virtual serial port is ready . First, debug by directly entering the command . We turn on KEIL MDK Of , Set to simulation mode . spot DEBUG. stay COMMAND Serial port input ：MODE   COM2   38400,  0,  8,  1

explain ：

MODE The function of the command is to set the parameters of the bound computer serial port . The basic usage is ：

MODE COMx baudrate, parity, databits, stopbits

among ：

COMx（x = 1,2,…） Represents the serial port number of the computer ;

baudrate Represents the baud rate of the serial port ;parity Represents the verification method ;

databits Represents the length of data bits ;

stopbits Represents the stop bit length .

for example ：MODE COM1 9600, n, 8, 1

Set the serial port 1. The baud rate is 9 600, No parity bit ,8 Bit data ,1 Bit stop bit .

MODE COM2 19200, 1, 8, 1

Set the serial port 2. The baud rate is 19 200, Odd check ,8 Bit data ,1 Bit stop bit .

4、 Click enter , Input again ASSIGN COM2 <S1IN> S1OUT

explain ：

COMx Represents the serial port of the computer , It can be COM1、COM2、COM3 Or others ;

inreg and outreg Represents the serial port of single chip microcomputer . For an ordinary single chip microcomputer with only one serial port , namely SIN and SOUT; For a single chip microcomputer with two or more serial ports , namely SnIN and SnOUT（n=0,1,… Serial port number of single chip microcomputer ）.

for example ：ASSIGN COM1 < SIN > SOUT

Connect the serial port of the computer 1 Serial port bound to MCU （ For single chip microcomputer with only one serial port ）.

ASSIGN COM2 < SIN > SOUT

Connect the serial port of the computer 2 Serial port bound to MCU 0（ For single chip microcomputer with multiple serial ports , Pay attention to the position of serial port number ）.

It should be noted that , The parentheses of parameters cannot be omitted , and outreg There are no parentheses .

5、 Then debug the program . You can see the serial port COM3 Print out the serial port 1 The data of the .