w83c553f Winbond Electronics Corp America, w83c553f Datasheet - Page 20

• Manufacturer Part Number: w83c553f
• Description: System I/o Controller With Pci Arbiter
• Manufacturer: Winbond Electronics Corp America

W83C553F
WINBOND SYSTEMS LABORATORY
Pin Name
GNT0# /
PIBREQ#
REQ0# /
PIBGNT#
GNT1# /
IDEREQ#
REQ1# /
IDEGNT#
ARBDIS# /
GNT2#
REQ2#
Pin #
26
25
28
27
16
17
Input/
Output
Output
Input
Output
Input
Input/
Output
Input
Table 2-3. PCI Arbiter Signals
Description
This is a multifunction pin. The W83C553F PCI-ISA bridge
(Function 0) asserts this signal to request the use of the PCI bus
when the on-chip PCI arbiter is disabled. This pin functions as
GNT0# when the on-chip PCI arbiter is enabled, allowing PCI
access to an external master.
This is a multifunction pin. An external arbiter asserts this signal to
grant the next PCI access to the PCI-ISA bridge (Function 0) when
the on-chip PCI arbiter is disabled. This pin functions as REQ0#
when the on-chip PCI arbiter is enabled.
This is a multifunction pin. The W83C553F IDE master (Function
1) asserts this signal to request the use of the PCI bus when the on-
chip PCI arbiter is disabled. This pin functions as GNT1# when the
on-chip PCI arbiter is enabled, allowing PCI access to an external
master.
This is a multifunction pin. An external arbiter asserts this signal to
grant the next PCI access to the IDE master when the on-chip PCI
arbiter is disabled. This pin functions as REQ1# when the on-chip
PCI arbiter is enabled.
When the on-chip PCI arbiter is enabled, it uses this pin to grant the
next PCI access. If a 2.2k Ohm resistor straps this pin to ground,
the PCI arbiter is disabled after power-up. This overrides the
strapping of PCI5TH# on pin 13.
When the on-chip PCI arbiter is enabled, external PCI masters use
this pin to request access to the PCI bus.
Pin Descriptions
17