CHAPTER 3 SPECIFICATIONS OF PCI HOST BRIDGE MACRO
Application Note U17121EJ1V1AN
37
(2) How to access PCI configuration register
•
Write
access
Set the access target register address to the PCI_CONFIG_ADD register
↓
Write the access target register setting value to the PCI_CONFIG_DATA register
•
Read
access
Set the access target register address to the PCI_CONFIG_ADD register
↓
Read the PCI_CONFIG_DATA register
3.4.3 PCI_CONTROL register
After reset: 07000100H R/W Offset address: 08H
31
24
23
17 16 15
8
7 5
4
3
2
1
0
PCI_PARKCNT
0 0 0 0 0 0 0
PCI_BPMO
D
E
PCI_REQ
0 0 0
PCI_RESET
0
TARGE
T
_EN
MEM_EN
IO_EN
Bit Name
R/W
Function
PCI_PARKCNT R/W
Sets the time for shifting to bus parking.
At the default value, bus parking is performed seven clocks after the bus status becomes IDLE.
The counter is started when FRAME# = High and IRDY# = High.
PCI_BPMODE R/W
Sets the bus parking master.
0: Limited to this macro
1: Master accessed last
PCI_REQ R/W
Enables/disables the REQ# signal (I_REQ_B1 to I_REQ_B7 pins) from the bus master.
Bit 0 of this field (bit 8 of the PCI_CONTROL register) is assigned to the PCI host bridge macro,
and is always 1.
0:
Disabled
1:
Enabled
PCI_RESET R/W
Sets the reset status of the PCI bus.
0: Reset status
1: Reset released
TARGET_EN R/W
Sets the operation of the PCI bus target of the PCI host bridge macro.
0: Do not respond to main memory (SDRAM) access from the PCI device
1: Respond to main memory (SDRAM) access from the PCI device
MEM_EN R/W
Enables/disables access from the CPU to the PCI memory area.
0: Access disabled
1: Access enabled
IO_EN R/W
Enables/disables access from the CPU to the PCI I/O area.
0: Access disabled
1: Access enabled
Содержание V850E/MA1
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