MSP430FR5994: Increasing read speed from a DS1620+ temperature sensor

Hi all

I have a MSP430FR5994 Launchpad and am integrating a DS1620+ temperature sensor from Maxim Integrated. I am currently bit banging (doesn't support I2C or SPI without extra hardware) to initialise the sensor to continuously convert, and then writing the 'read temperature' command in an endless loop. I am toggling a pin to check the speed on an oscilloscope. When writing the 'read' command alone, this occurs at a rate of 40kHz. When I actually store the data, this drops to 10KHz, when I expected it to reach ~20kHz (writing an 8 bit command, reading 9 bit data). Does anyone know why this may be the case? Speed is a critical factor for this project, so I need to make this as fast as possible.

I have noted that the datasheet for the sensor states that the maximum clock frequency is 1.75MHz, could this possibly a factor (Although I wouldn't have thought so since I don't reach these speeds)?

Additionally, I have set the main clock to 8MHz, but when I double this to 16MHz, the speed approximately halves (to below 5kHz when storing data). I cannot understand why this is the case, as this also happens when using an SD card in another program. I have noted that FRAM can only operate at a maximum speed of 8MHz, could something similar be happening in these cases?

I've attached the endless loop, with data storage, below.

    while (1){
        
        //------Start talking------//
        
        P4OUT = 0x08;   //CLK high

        P2OUT = 0x20;   // Active on RST high
    
        // Send 'read temp' command (0b 1010 1010, LSB first)
    
        P4OUT = 0x08;
        P4OUT = 0x00;
        P4OUT = 0x08;

        P4OUT = 0x0C;
        P4OUT = 0x04;
        P4OUT = 0x0C;
    
        P4OUT = 0x08;
        P4OUT = 0x00;
        P4OUT = 0x08;
    
        P4OUT = 0x0C;
        P4OUT = 0x04;
        P4OUT = 0x0C;
    
        P4OUT = 0x08;
        P4OUT = 0x00;
        P4OUT = 0x08;
    
        P4OUT = 0x0C;
        P4OUT = 0x04;
        P4OUT = 0x0C;
    
        P4OUT = 0x08;
        P4OUT = 0x00;
        P4OUT = 0x08;
    
        P4OUT = 0x0C;
        P4OUT = 0x04;
        P4OUT = 0x0C;
    
        //------Start reading------//
        
        P4DIR = 0x08;   // Set P4.2 (DQ) as an input
    
        // Collect bits
        for(n=0;n<9;n++){
            P4OUT = P4IN & 0xF7;
            int status = P4IN & 0x04;
    
            if (status == 0x04){
                rawData[n] = 1;
            }
            if (status == 0x00){
                rawData[n] = 0;
            }
            P4OUT = P4IN | 0x08;
        }
    
        P4DIR = 0x0C;   // Set P4.2 (DQ) as an output
        
        P2OUT = 0x00;   // RST low
        
        //------Stop talking------//
    
        P8OUT ^= 0x02;  // toggle oscilloscope pin
    }