Intergraph StudioZ RAX System Reference Manual page 84

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Palette DAC
The palette DAC operates up to 175 MHz and converts the digital RGB data in the frame buffer to
analog signals for the monitor. The device includes two fully programmable phase-locked loop clock
sources for both the memory clock and the pixel clock.
Window RAM
Window RAM (WRAM) is the video memory used by the MGA-2064W. The graphics frame buffer
consists of two 256K x 32 WRAM components for 2 MB of video memory. WRAM is a dual-ported
video memory specially designed to accommodate common drawing functions, offering higher graphics
performance at a lower cost than standard Video RAM.
Starting with 2 MB WRAM, a 2 MB or 6 MB WRAM mezzanine module can be added for improved
video performance. 8 MB of WRAM is the maximum amount configurable. Memory above 2 MB
increases the number of colors available at each resolution, enabling you to work in true color mode at
higher resolutions. Increased WRAM also improves color acceleration by providing extra caching
memory for storing off-screen fonts and images.
SCSI Controller
The SCSI controller is the Adaptec Ultra SCSI Adapter (AIC-7860), which provides a single-ended bus
for SCSI-1, Fast SCSI-2, and Ultra SCSI devices. The SCSI bus is dedicated to the hard disk drives
and CD-ROM drive. The SCSI bus actively terminates on the system board and at the end of the
internal SCSI cable. The AIC-7860 supports low-speed devices to allow legacy SCSI devices to be
used with the system. By default, the controller functions in Fast SCSI-2 mode rather than Ultra mode.
Super I/O Controller
The I/O Expansion Board utilizes a Standard Microsystems Corporation (SMC) Super I/O Controller
(FDC37C932) to integrate mouse, keyboard, serial, parallel (multi-mode), floppy (2.88 MB), and Real-
Time Clock (RTC) functions into one chip.
The FDC37C932 supports four serial ports via two external port connectors (COM 1 and COM 2).
COM1 can be configured as COM1 or COM3; COM2 can be configured as COM2 or COM4. The
serial ports use the system I/O addresses shown below.
Port
COM1
COM2
COM3
COM4
The addresses for each serial port can be configured in AMIBIOS Setup, as described in the System
Setup. Do not assign more than one device to the same COM port number. Serial port problems occur
because a serial port and another device are assigned to the same COM number. The system and the
connected serial device must be set to the same communications parameters (baud rate, parity, number
of data bits, and number of stop bits). Refer to the serial device documentation for information about
setting these parameters.
Addresses Interrupts
3F8-3FF IRQ4
2F8-2FF IRQ3
3E8-3EF IRQ4
2E8-2EF IRQ3