The MIC-3611/3611R is a 6U/3U sized 4-port RS-422/485 CompactPCI Comm. Card, Series communication cards which complies with PICMG 2.0 R2.1 CompactPCI specifications. All channels are addressed in a continuous 32 byte I/O block for simplified software access, All channels may also share one PCI interrupt status register is available for determining the interrupt source. <br><br> The MIC-3611/3611R comes standard with 16C954 UARTs containing 128 byte FIFOs which are available as an option. There upgraded FIFOs greatly reduce CPU overhead and are an ideal choice for heavy multitasking environments.