MCU C51 serial port interrupt reception and transmission test routine (including communication protocol implementation)-EEWORLD

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Communication protocol: The first byte, MSB is 1, which is the first byte mark, the second byte, MSB is 0, which is the non-first byte mark, and so on... The last byte is the XOR checksum of the last 7 bits of the previous bytes.
Test method: You can write 95 10 20 25 in the sending box of the serial port debugging assistant, and select hexadecimal sending, and select hexadecimal display in the receiving box. If 95 10 20 25 is received every time it is sent, it means the test is successful.

//This is a microcontroller C51 serial port receiving (interrupt) and sending routine, which can be used to test the interrupt reception
//and query sending of the 51 microcontroller. In addition, I think it is not necessary to use interrupts for sending, because the program overhead is the same

#include
#include

#define INBUF_LEN 4 //data length

unsigned char inbuf1[INBUF_LEN];
unsigned char checksum,count3;
bit read_flag= 0 ;

void init_serialcomm( void )
{
SCON = 0x50 ; //SCON: serail mode 1, 8-bit UART, enable ucvr
TMOD |= 0x20 ; //TMOD: timer 1, mode 2, 8-bit reload
PCON |= 0x80 ; //SMOD=1;
TH1 = 0xF4 ; //Baud:4800 fosc=11.0592MHz
IE |= 0x90 ; //Enable Serial Interrupt
TR1 = 1 ; // timer 1 run
// TI=1;
}

//Send a character to the serial port
void send_char_com( unsigned char ch)
{
SBUF=ch;
while (TI== 0 );
TI= 0 ;
}

//Send a string to the serial port, strlen is the length of the string void
send_string_com( unsigned char *str, unsigned int strlen)
{
unsigned int k= 0 ;
do
{
send_char_com(*(str + k));
k++;
} while (k < strlen);
} //Serial port receive interrupt function void serial () interrupt 4 using 3 { if (RI) { unsigned char ch; RI = 0 ; ch=SBUF; if (ch> 127 ) { count3= 0 ; inbuf1[count3]=ch; checksum= ch- 128 ; } else { count3++; inbuf1[count3]=ch; checksum ^= ch; if ( (count3==(INBUF_LEN- 1 )) && (!checksum) ) { read_flag= 1 ; //If the serial port receives data up to INBUF_LEN and the verification is correct, //set the data read flag } } } } main() { init_serialcomm(); //Initialize the serial portwhile ( 1 ) { if (read_flag) //If the data read flag is set, send the read number from the serial port { read_flag= 0 ; //Clear the data read flag send_string_com(inbuf1,INBUF_LEN); } } }

Reference address：MCU C51 serial port interrupt reception and transmission test routine (including communication protocol implementation)

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