PIC30F4013+PIC16C72兩顆單片機製作簡易PLC

洪嵐峰

你可以根據需要進行修改：

PIC30F4013端：

// Define communication pins
#define STATUS_PIN  RB5
#define DATA_IN_PIN RB3
#define DATA_OUT_PIN RB4
#define CLOCK_PIN   RB2

// Define data buffer size
#define BUFFER_SIZE 16

// Define instruction codes
#define READ_INPUTS  0x01
#define WRITE_OUTPUT 0x02

// Define I/O port addresses
#define INPUT_PORT  PORTB
#define OUTPUT_PORT LATB

void main() {
    // Set communication pins as output
    TRISBbits.TRISB2 = 0; // Clock pin
    TRISBbits.TRISB4 = 0; // Data out pin
   
    // Set communication pins as input
    TRISBbits.TRISB5 = 1; // Status pin
    TRISBbits.TRISB3 = 1; // Data in pin
   
    // Initialize input/output ports
    TRISD = 0xFFFF; // Set all pins as input
    TRISC = 0x0000; // Set all pins as output
   
    // Initialize data buffer
    unsigned char buffer[BUFFER_SIZE];
    for (int i = 0; i < BUFFER_SIZE; i++) {
        buffer[i] = 0;
    }
   
    while (1) {
        // Wait for read inputs instruction
        while (1) {
            if (receive_instruction() == READ_INPUTS) {
                break;
            }
        }
        
        // Read inputs and store in buffer
        for (int i = 0; i < BUFFER_SIZE; i++) {
            buffer[i] = INPUT_PORT;
        }
        
        // Send data back to master
        send_data(buffer, BUFFER_SIZE);
        
        // Wait for write output instruction
        while (1) {
            if (receive_instruction() == WRITE_OUTPUT) {
                break;
            }
        }
        
        // Read data from master and write to outputs
        for (int i = 0; i < BUFFER_SIZE; i++) {
            OUTPUT_PORT = buffer[i];
        }
    }
}

// Function to receive instruction from master
unsigned char receive_instruction() {
    unsigned char instruction = 0;
   
    // Wait for status pin to go low
    while (STATUS_PIN);
   
    // Receive instruction byte
    for (int i = 0; i < 8; i++) {
        // Wait for clock pulse
        while (!CLOCK_PIN);
        
        // Read data in pin
        instruction |= (DATA_IN_PIN << i);
        
        // Wait for clock pulse
        while (CLOCK_PIN);
    }
   
    // Set data out pin low
    DATA_OUT_PIN = 0;
   
    return instruction;
}

// Function to send data to master
void send_data(unsigned char* data, int size) {
    // Set data out pin high
    DATA_OUT_PIN = 1;
   
    // Send data bytes
    for (int j = 0; j < size; j++) {
        unsigned char byte = data[j];
        
        // Send data byte
        for (int i = 0; i < 8; i++) {
            // Set clock pin high
            CLOCK_PIN = 1;
            
            // Send bit
            DATA_OUT_PIN = ((byte >> i) & 0x01);
            
            // Wait for clock pulse
            __delay_us(1);
            
            // Set clock pin low
            CLOCK_PIN = 0;
            // Wait for clock pulse
        __delay_us(1);
    }
}

// Set data out pin low
DATA_OUT_PIN = 0;
}



PIC16C72端：


// Define communication pins
#define STATUS_PIN  RC0
#define DATA_IN_PIN RC2
#define DATA_OUT_PIN RC1
#define CLOCK_PIN   RC3

// Define data buffer size
#define BUFFER_SIZE 16

// Define instruction codes
#define READ_INPUTS  0x01
#define WRITE_OUTPUT 0x02

// Define I/O port addresses
#define INPUT_PORT  PORTB
#define OUTPUT_PORT LATB

void main() {
    // Set communication pins as output
    TRISCbits.TRISC1 = 0; // Data out pin
    TRISCbits.TRISC3 = 0; // Clock pin
   
    // Set communication pins as input
    TRISCbits.TRISC0 = 1; // Status pin
    TRISCbits.TRISC2 = 1; // Data in pin
   
    // Initialize input/output ports
    TRISB = 0xFFFF; // Set all pins as input
    TRISA = 0x0000; // Set all pins as output
   
    // Initialize data buffer
    unsigned char buffer[BUFFER_SIZE];
    for (int i = 0; i < BUFFER_SIZE; i++) {
        buffer[i] = 0;
    }
   
    while (1) {
        // Send read inputs instruction to slave
        send_instruction(READ_INPUTS);
        
        // Receive data from slave
        receive_data(buffer, BUFFER_SIZE);
        
        // Write inputs to output ports
        for (int i = 0; i < BUFFER_SIZE; i++) {
            OUTPUT_PORT = buffer[i];
        }
        
        // Send write output instruction to slave
        send_instruction(WRITE_OUTPUT);
        
        // Read data from master and store in buffer
        for (int i = 0; i < BUFFER_SIZE; i++) {
            buffer[i] = INPUT_PORT;
        }
        
        // Send data back to master
        send_data(buffer, BUFFER_SIZE);
    }
}

// Function to send instruction to slave
void send_instruction(unsigned char instruction) {
    // Set data out pin low
    DATA_OUT_PIN = 0;
   
    // Send instruction byte
    for (int i = 0; i < 8; i++) {
        // Wait for clock pulse
        while (CLOCK_PIN);
        
        // Send bit
        DATA_OUT_PIN = ((instruction >> i) & 0x01);
        
        // Wait for clock pulse
        while (!CLOCK_PIN);
    }
   
    // Wait for status pin to go high
    while (!STATUS_PIN);
}

// Function to receive data from slave
void receive_data(unsigned char* data, int size) {
    // Set data out pin high
    DATA_OUT_PIN = 1;
   
    // Receive data bytes
    for (int j = 0; j < size; j++) {
        unsigned char byte = 0;
        
        // Receive data byte
        for (int i = 0; i < 8; i++) {
            // Wait for clock pulse
            while (!CLOCK_PIN);
            
            // Read data in pin
            byte |= (DATA_IN_PIN << i);
            
            // Wait for clock pulse
            while (CLOCK_PIN);
        }
        
        // Store data byte in buffer
        data[j] = byte;
    }
   
    // Set data out pin low
    DATA_OUT_PIN = 0;// Function to send data to master
}

void send_data(unsigned char* data, int size) {
// Set data out pin high
DATA_OUT_PIN = 1;

// Send data bytes
for (int j = 0; j < size; j++) {
    unsigned char byte = data[j];
   
    // Send data byte
    for (int i = 0; i < 8; i++) {
        // Wait for clock pulse
        while (CLOCK_PIN);
        
        // Send bit
        DATA_OUT_PIN = ((byte >> i) & 0x01);
        
        // Wait for clock pulse
        while (!CLOCK_PIN);
    }
}

// Set data out pin low
DATA_OUT_PIN = 0;
}



在設計PLC時，需要仔細考慮各種因素，例如通信協議、故障處理、安全性等。