Advantech PCI-1602UP 2-port RS-422/485 compact universal PCI communication card provides 2 independent RS-422/485 ports. The high-performance 16PCI952 and 16PCI954 UART chips with 128 byte FIFO are used, which can greatly reduce the CPU load and are very suitable for use in multitasking environments. In addition, these boards comply with the compact PCI MD1 standard. Compact PCI has the same signal protocol and electronic definition as standard PCI, but its size is smaller than standard PCI cards.