National Instruments 779147-01 Serial Interface Device 

National Instruments part number 779147-01 is an identifying part number for the PCI-8430/8, an RS-232 Serial Interface Device. This instrument is structured for high-speed communication with RS232 devices. It supports high-performance DMA transfers, multithreading, and multiprocessor systems. 

NI serial interfaces appear as standard COM ports, ensuring compatibility with programs that utilize serial communications. This device comes with 8 ports and a maximum baud rate of 1000 kbits/s, along with a 68-pin SCSI connector and a FIFO size of 128 bytes. It features a DMA channel consisting of two FIFOs: one on the host PC and one on the FPGA target. After creating a DMA FIFO, the user writes block diagram code to transfer data to and from the appropriate buffer. For example, if data is being transferred from the FPGA to the host, code is written on the FPGA to send data to the buffer, while code on the host reads data from it. Modern PCs are capable of customized I/O and interrupt data transfers. 

DMA transfers increase system throughput by using dedicated hardware to move data directly into system memory. This method frees the processor from the task of moving data, allowing it to focus on processing tasks instead. 

Through National Instruments driver programming, the DMA schedules to exchange waveform information over the PC transport are improved, along these lines giving the capacity to exchange information as quickly as would be prudent. Each DMA controller diverter has a First-in-First-Out (FIFO) memory stockpiling and free procedures for filing and exhausting the FIFO. The device has a power requirement of +5 VDC at 1.3 A typical and 1.9 A maximum.