ftdi_read_data returns immediately without waiting for timeout and with no data

[mxb7642 <maxbobrov@xxxxxxxxx>]

When executing an ftdi_read_data, the command always returns extremely
quickly (I've timed it and it takes 0ms when the timeout is set to 50sec)
without waiting the set timeout time and always returns 0 bytes of data. My
code is below. Why is this happening? I assume this is not the intended
functionality? Thanks! 

int main(void){ 
        bool success = false; 
        int status; 

        // Try to connect 
        status = ftdi_init(&ftdic); 
        success = (status==0); 

        if(success){ 
                status = ftdi_usb_open(&ftdic, VENDOR_ID, PRODUCT_ID); 
                success = (status==0); 
        } 

        // Set baud rate 
        if(success){ 
                status = ftdi_set_baudrate(&ftdic, 2400); 
                success = (status==0); 
        } 

        // Set bit mode to serial 
        if(success){ 
                status = ftdi_set_bitmode(&ftdic, 0xFF, BITMODE_RESET); 
                success = (status==0); 
        } 

        // Set data characteristics to 8 bits, 1 stop, no parity 
        if(success){ 
                status = ftdi_set_line_property(&ftdic, BITS_8, STOP_BIT_1,
NONE); 
                success = (status==0); 
        } 

        // Set flow control to none 
        if(success){ 
                status = ftdi_setflowctrl(&ftdic, SIO_DISABLE_FLOW_CTRL); 
                success = (status==0); 
        } 

        // Set read data chunk size 
        if(success){ 
                status = ftdi_read_data_set_chunksize(&ftdic, 2); 
                success = (status==0); 
        } 

        // Set write data chunk size 
        if(success){ 
                status = ftdi_write_data_set_chunksize(&ftdic, 4); 
                success = (status==0); 
        } 

        // Set latency timer 
        if(success){ 
                status = ftdi_set_latency_timer(&ftdic, 1); 
                success = (status==0); 
        } 

        // Set maximum packet size 
        ftdic.max_packet_size = 4; 

        // Clear Tx and Rx buffers 
        if(success){ 
                status = ftdi_usb_purge_buffers(&ftdic); 
                success = (status==0); 
        } 

        if(!success){ 
                ftdi_free(&ftdic); 
        } 

        int RxBytesRead; 
        uchar RxBuffer[2]; 
        ftdic.usb_read_timeout = 50000; 
        printf("%d\t%d\t%d\n", ftdic.usb_read_timeout,
ftdic.usb_write_timeout, ftdic.max_packet_size); 
        clock_t t1, t2, ms; 
        while(1){ 
                t1 = clock(); 
                RxBytesRead = ftdi_read_data(&ftdic, RxBuffer,
sizeof(RxBuffer)); 
                t2 = clock(); 
                ms = (t2-t1)*1000/CLOCKS_PER_SEC; 
                if(RxBytesRead==0) 
                        printf("timeout"); 
                else if(RxBytesRead<0) 
                        printf("error"); 
                else 
                        printf("%0X\t%0X", RxBuffer[0], RxBuffer[1]); 
                printf("\t%d\n", ms); 
        } 

        return success; 
} 

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