HP (Hewlett-Packard) 520 5/XX Personal Computer User Manual


 
53
2 System Board - (SiS Chipset) (Part Number: D4051-63001)
Devices on the ISA Bus
Feature Summary
Function Features
Floppy disk controller Software compatible with the DP8473, the 765A, and the
N82077
16-byte FIFO (default disabled)
Burst and non-burst modes
Perpendicular recording drive support
New high-performance internal digital data separator (no
external filter components required)
Low-power CMOS with enhanced power-down mode
Automatic media-sense support
UARTs Software compatible with the PC16550A and PC16450
A modifiable address that is referenced by a 16-bit programma-
ble register.
13 IRQ channel options.
Shadow register support for write-only bits.
Four 8-bit DMA options for UART2.
Bidirectional parallel port Enhanced Parallel Port (EPP) compatible
Extended Capabilities Port (ECP) compatible
Bidirectional under either software or hardware control
Demand mode DMA support.
Selection of internal pull-up or pull-down resistor for Paper End
(PE) pin.
Reduction of PCI bus utilization by supporting a demand DMA
mode mechanism and a DMA fairness mechanism.
Includes protection circuit against damage caused when printer
is switched on, or operated at higher voltages.
Output buffers that can sink and source 14 mA.
Three general purpose pins for three
separate chip select signals
Programmed for game port control.
Chip Select 0 (CS0) signal produces open drain and is powered
by the V
CCH
.
Chip Select 1 (CS1) and 2 (CS2) signals have push-pull buffers
and are powered by the main V
DD
.
Decoding of chip select signals depends on the address and the
Address Enable (AEN) signal, and can be qualified using the
Read (RD) and Write (WR) signals.
Enhanced power management Special configuration registers for power down
Reduced current leakage from pins.
Low-power CMOS technology.
Ability to shut off clocks to all modules.