[tutorial 15 of trio basic from introduction to proficiency] trio free serial communication

     Dear friends , Hello everyone ！ Today brings you the most basic functions , A serial port communication . I believe this is no stranger .modbusRTU,Membus And other protocols are based on the software communication protocol built on the serial port . I hope this blog will bring you a little harvest , Old bird can skip this chapter ...

    Don't talk too much , Today, let's talk about the most basic communication function , Ten thousand tall buildings rise from the ground .

Before talking about serial communication , Let's list the relevant instructions ：

1.

GET Get a character from the data buffer stream

Examples are as follows ：

// Get a character and store it in a temporary variable

DIM get_str ASINTEGER

GET #2,get_str

2.

PRINT Send data by character stream

Examples are as follows ：

// Send a string

PRINT #2,"This is Test:"

// Send a character

PRINT #2,CHR(48);

PRINT #2,CHR($30);

3.

ADDRESS Serial port site address

4.

SETCOM Set serial communication parameters

Let's focus on setcom

Examples are as follows ：(1) Set up local site 2, Baud rate 9600,8 Data bits ,1 Stop bits , Even check ,232 Hardware , Free port communication

ADDRESS=2

SETCOM(9600,8,1,2,1,0)

(2) Set up local site 1, Baud rate 9600,8 Data bits ,1 Stop bits , Even check ,485 Hardware , Free port communication

ADDRESS=1

SETCOM(9600,8,1,2,2,0,0,3,0)

The preparatory knowledge is finished , Then let's look at the code , See the implementation effect .

DIM get_str,data_num AS INTEGER

ADDRESS=1
'RS232
SETCOM(9600,8,1,2,1,0)
'RS485
SETCOM(9600,8,1,2,2,0,0,3,0)
WA(100)

WHILE TRUE
    PRINT #2,"This is Test:"
    PRINT #2,data_num;CHR(13);CHR(10);
    WA(100)
    IF KEY #2 THEN
        WHILE KEY #2
            GET #2,get_str
            PRINT #2,CHR(get_str);
        WEND
    ENDIF
    data_num=data_num+1
WEND

matters needing attention ： Baud rate of communication between sender and receiver 、 Stop bit 、 The check bits need to be consistent .

Execution effect

Sending and receiving are normal

Dear brothers , Brothers and sisters , That's all for today , Thank you for reading ...