12. Register Descriptions
262
PowerSpan II User Manual
80A1010_MA001_09
Integrated Device Technology
www.idt.com
12.5.10
PCI-1 Miscellaneous 1 Register
Register Name: P1_MISC1
Register Offset: 0x03C
PCI
Bits
Function
PB
Bits
31-24
MAX_LAT
0-7
23-16
MIN_GNT
8-15
15-08
INT_PIN
16-23
07-00
INT_LINE
24-31
P1_MISC1 Description
Name
Type
Reset
By
Reset
State
Function
MAX_LAT [7:0]
R/W
P1_RST
0
Maximum Latency
This field specifies how often the device needs access to
the PCI bus.
No special latency requirements
MIN_GNT [7:0]
R/W
P1_RST
0
Minimum Grant
This field indicates how long a master wants to retain
bus ownership whenever it initiates a transaction.
No special requirements
INT_PIN [7:1]
R
P1_RST
0
Interrupt Pin (7 to 1)
This field represents general purpose interrupt pins.
Interrupt pins are active low and, when configured as
input, are sampled on three successive processor bus
clock edges to ensure appropriate setting of a status bit.
Each pin is bidirectional, open drain, active low and level
sensitive. The input/output character of each interrupt
pin is controlled through a corresponding bit in the
“Interrupt Direction Register” on page 347
. Each pin can
be configured as either an input or output. All pins are
configured as inputs by default.
INT_PIN [0]
R/WPB
P1_RST
1
EEPROM
Interrupt Pin
This interrupt pin is used to enable PCI interrupts. If this
bit is not set, PowerSpan II does not use PCI interrupts.
Setting this bit enables a single function PCI device to
use INTA#.
0 = The device does not use any PCI interrupts
1 = The device uses INTA_