The National Instruments PCI-485I/2 (Part Number: 777853-02) is a highly versatile 2-channel isolated serial interface designed for seamless communication with serial port-equipped instruments. This asynchronous interface supports daisy-chaining up to 31 devices via a standard serial cable, facilitating extensive system configurations. The PCI-485I/2 features a DB-9 male connector with allocations for both RS232 and RS485 connections, ensuring compatibility with a wide range of devices. With a maximum transfer rate of 460.8 kb/s and a 64-byte FIFO buffer, the device offers efficient data handling for demanding applications. The channels on this interface are optically isolated, enhancing protection against electrical disturbances. Built for 3.3 V and 5 V PCI slots, the PCI-485I/2 supports a plug-and-play installation process that simplifies configuration without the need for physical switches. Under typical operational conditions, it consumes 800 mA from the PCI bus, with a maximum draw of 1300 mA. The PCI-485I/2 is compatible with Windows 2000/NT/XP/Me/9x-based personal computers, allowing it to function as a standard serial port for existing applications. Furthermore, it can be integrated with development environments such as Visual C++, Visual Basic, and NI LabVIEW. The device includes integrated data line ESD protection, safeguarding against surges of up to 15 kV. The designation "I" in PCI-485I/2 signifies its isolation capabilities, distinguishing it from the non-isolated standard model, PCI-485/2 (Part Number: 777641-02). Additional variations include the 4-channel PCI-485/4 (Part Number: 777641-04) and the 8-channel PCI-485/8. The technical specifications support diverse usage scenarios, making the PCI-485I/2 an ideal choice for professionals seeking reliable serial communication solutions.