Diamond Systems (Mountain View, CA) has introduced a rugged, low cost 4-port multiprotocol opto-isolated serial port module in the popular PCIe MiniCard form factor measuring 30 x 51mm. The DS-MPE-SER4OPT offers 4 RS-232/RS-485 opto-isolated serial ports. Each port offers 16C550 compatibility and ultra-deep 256-byte TX/RX FIFOs. Maximum data rates are 1Mbps in RS-232 mode and 10Mbps in RS-485 mode. The board is available preconfigured for 4 RS-232 ports, 4 RS-485 ports, or a combination of 2 RS-232 and 2 RS-485 ports. I/O signals are provided on two miniature latching connectors, with 2 ports per connector. Each pair of serial ports on the DS-MPE-SER4OPT offers up to 500V isolation from the system ground. Extended temperature capability of -40°C to +85°C enables the board to operate in environments with extreme temperature swings, such as vehicles or outdoor installations. In addition, the board may be custom-configured with 0-ohm resistors in place of jumper blocks for increased ruggedness in high-vibration environments.