B-2 Dell PowerEdge 4200 Systems User’s GuideFigure B-1. I/O Ports and ConnectorsAdding an Expansion Card ContainingSerial or Parallel PortsThe computer system has an autoconfiguration capabilityfor the serial ports. This feature lets you add an expansioncard containing a serial port that has the same designationas one of the built-in ports, without having to reconfigurethe card. When the computer detects the duplicate serialport on the expansion card, it remaps (reassigns) the built-in port to the next available port designation.Both the new and the remapped COM ports share thesame interrupt request (IRQ) setting, as follows:COM1, COM3: IRQ4 (shared setting)COM2, COM4: IRQ3 (shared setting)These COM ports have the following I/O addresssettings:COM1: 3F8hCOM2: 2F8hCOM3: 3E8hCOM4: 2E8hFor example, if a technician adds an internal modem cardwith a port configured as COM1, the computer then seeslogical COM1 as the address on the modem card. Itautomatically remaps the built-in serial port that was des-ignated as COM1 to COM3, which shares the COM1IRQ setting. (Note that when you have two COM portssharing an IRQ setting, you can use either port as neces-sary but you may not be able to use them both at the sametime.) If you install one or more expansion cards withserial ports designated as COM1 and COM3, the corre-sponding built-in serial port is disabled.Before adding a card that remaps the COM ports, checkthe documentation that accompanied your software tomake sure that the software can be mapped to the newCOM port designation.To avoid autoconfiguration, the technician may be able toreset jumpers on the expansion card so that the card’sport designation changes to the next available COMnumber, leaving the designation for the built-in port as is.Alternatively, you can disable the built-in ports throughthe System Setup program. The documentation for yourexpansion card should provide the card’s default I/Ovideo connector(JVGA)server-managementserial port connector(REMOTE)parallel portconnector(PARALLEL)serial port 2connector(SERIAL2)serial port 1connector(SERIAL1)mouse connector(MOUSE)keyboard connector(KYBD)
