The LPCI-COM-4SM is a four-port asynchronous serial communication card designed for use in PCI bus computers. The cards support RS-232, RS-422, and/or RS-485 communications which can be selected on a port by port basis. The cards are 6.6 inches in length and 2.21 inches seated height and may be installed in any 3.3 or 5-volt PCI or PCI-X expansion slot. A regular profile mounting bracket is installed for use in standard size computers, while a low profile bracket is provided for low profile computers (such as thin-client and high-density rack-mount servers). The cards are supplied with an eight-connector DB-9 breakout cable (no external breakout box required). The LPCI line has been designed for use in retail, hospitality, postal automation, and POS system applications and industries such as gaming and defense where space is a valuable resource.
A type 16L788 octal UART is used as the asynchronous communication element. This includes 64-byte transmit/receive FIFO buffers to protect against lost data in multitasking systems while maintaining compatibility with the original IBM serial port (100% compatible with standard Windows COM port drivers).
Crystal oscillators located on the card permit precise baud rate capability up to 115,200. Higher speeds, up to 921k baud, are achieved by changing a jumper on the card. The driver/receivers used for RS-485 & RS-422 are type SP491, and are capable of driving long communication lines at high baud rates. They can drive up to ±60 mA on balanced lines and receive inputs as low as 200 mV differential signal superimposed on common mode noise of +12V to -7V. In case of communication conflict, the driver/receivers feature thermal shutdown.