void setup() {
    chipName("SN74HC595"); // 8-bit shift register
    logicFamily(TTL);

    pin(1, "Q1", THREE_STATE);
    pin(2, "Q2", THREE_STATE);
    pin(3, "Q3", THREE_STATE);
    pin(4, "Q4", THREE_STATE);
    pin(5, "Q5", THREE_STATE);
    pin(6, "Q6", THREE_STATE);
    pin(7, "Q7", THREE_STATE);
    pin(8, "GND", GROUND);
    pin(9, "Q7S", THREE_STATE);
    pin(10, "MR", INPUT, LINE_OVER);
    pin(11, "SHCP");
    pin(12, "STCP");
    pin(13, "OE", OUTPUT, LINE_OVER);
    pin(14, "DS");
    pin(15, "Q0", THREE_STATE);
    pin(16, "VCC", POWER);
}

bool q[8];
bool qs[8];
bool lastShcp = false;
bool lastStcp = false;

void loop() {
    // Read the current states of control pins
    // Read SHCP (shift clock)
    bool shcp = digitalRead(11);
    // Detect rising edge of SHCP
    bool shcpRise = !lastShcp && shcp;
    // Read STCP (storage clock)
    bool stcp = digitalRead(12);
    // Detect rising edge of STCP
    bool stcpRise = !lastStcp && stcp;
    // Read OE (output enable)
    bool noe = digitalRead(13);
    // Read MR (master reset)
    bool nmr = digitalRead(10);
    // Read DS (serial data input)
    bool ds = digitalRead(14);

    // Set the three-state mode based on OE (output enable) state
    // Q7S oub
    pinThreeStateMode(9, noe ? HIGH_Z : LOW_IMPEDANCE);
    // Set the three-state mode for pins Q1 to Q7 based on OE (output enable) state
    for (int i = 1; i <= 7; i++)
        pinThreeStateMode(i, noe ? HIGH_Z : LOW_IMPEDANCE);
    pinThreeStateMode(15, noe ? HIGH_Z : LOW_IMPEDANCE);

// Reset all outputs when Storage Clock (STCP) rises and Master Reset (MR) is not active
    if (stcpRise && !nmr) {
        // Clear Q7S
        digitalWrite(9, LOW);
        for (int i = 0; i < 8; i++)
            // Clear both qs and q arrays
            qs[i] = q[i] = false;
        // Set Q1 to Q7 TO low
        for (int i = 1; i <= 7; i++)
            digitalWrite(i, LOW);
        // Set Q0 to low
        digitalWrite(15, LOW);
    }

    // Handle shift and storage of data when Shift Clock (SHCP) rises and Master Reset (MR) is active
    if (shcpRise && nmr) {
        // On STCP rise, copy shifted data into output array and update Q pins
        if (stcpRise) {
            for (int i = 0; i < 8; i++)
                q[i] = qs[i];
            // Update Q1 to Q7 pins
            for (int i = 1; i <=7; i++)
                digitalWrite(i, q[i]);
            // Update Q0 pin
            digitalWrite(15, q[0]);
        }
        // Update Q7S pin
        digitalWrite(9, qs[7]);
        // Shift the qs array
        for (int i = 7; i >= 1; i--)
            qs[i] = qs[i-1];
        // Load the new serial data into the first position of qs array
        qs[0] = ds;
        log((int)qs[0]);
    }

    // Update output pins whe Storage Clock (STCP) rises and Master Reset (MR) is active
    if (!shcpRise && stcpRise && nmr) {
        for (int i = 0; i < 8; i++)
            // Copy shifted data into output array
            q[i] = qs[i];
        // Update Q1 to Q7 pins
        for (int i = 1; i <= 7; i++)
            digitalWrite(i, q[i]);
        // Update Q0 oub
        digitalWrite(15, q[0]);
    }

    // Update the previous states of Shift Clock (SHCP) and Storage Clock (STCP)
    lastShcp = shcp;
    lastStcp = stcp;
}