System Overview 1-11Real-Time Clock/CalendarThe Y2K compliant real-time clock provides system clock/calendar information storedin a non-volatile memory (NVRAM). The real-time clock battery provides powerbackup for the real-time clock.BIOSA BIOS and Setup Utility are located in the Flash EPROM on the system board andinclude support for system setup and PCI/ISA Plug-and-Play auto-configuration. Anumber of security, reliability, and management features also have been incorporated tomeet vital server needs.IDE ControllerIDE is a 16 bit interface for intelligent disk drives with disk controller electronicsonboard. The PCI/ISA/IDE Accelerator, also known as PIIX4e, is a multifunctiondevice on the server board that acts as a PCI based Fast IDE controller. The devicecontrols: PIO and IDE DMA/bus master operations Mode 4 timings Transfer rates up to 33 MB/s Buffering for PCI/IDE burst transfers Master/slave IDE mode Up to two devices per channel; two channels, IDE0 and IDE1The IDE controller provides support for the internally mounted CD-ROM and anoptional tape device.Network ControllerThe system board includes a 10BASE-T/100BASE-TX network controller based on theIntel 82559 single chip Fast Ethernet PCI Bus Controller. As a PCI bus master, thecontroller can burst data at up to 132 MB/sec. The controller contains two receive andtransmit FIFO buffers that prevent data overruns or underruns while waiting for accessto the PCI bus. The controller has the following: 32-bit PCI bus master interface (direct drive of bus), compatible with PCI BusSpecification, Revision 2.1 Chained memory structure with improved dynamic transmit chaining forenhanced performance Programmable transmit threshold for improved bus utilization Early receive interrupt for concurrent processing of receive data On-chip counters for network management
