GD82551ER Intel, GD82551ER Datasheet - Page 55

• Manufacturer Part Number: GD82551ER
• Manufacturer: Intel

Specifications of GD82551ER

• Operating Supply Voltage (typ): 3.3V
• Operating Supply Voltage (min): 3V
• Operating Supply Voltage (max): 3.6V
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 196
• Lead Free Status / RoHS Status: Not Compliant

7.1.9.1
7.1.9.2
7.1.9.3
7.1.9.4
7.1.10
7.1.11
Datasheet
CSR Memory Mapped Base Address Register
The 82551ER requires one BAR for memory mapping. Software determines which BAR, memory
or I/O, is used to access the 82551ER CSR registers.
The memory space for the 82551ER CSR Memory Mapped BAR is 4 KB. The space is marked as
not prefetchable and is mapped anywhere in the 32-bit memory address space.
CSR I/O Mapped Base Address Register
The 82551ER requires one BAR for I/O mapping. Software determines which BAR, I/O or
memory, is used to access the 82551ER CSR registers. The I/O space for the 82551ER CSR I/O
BAR is 64 bytes.
Flash Memory Mapped Base Address Register
The Flash Memory BAR is a Dword register. The 82551ER physically supports a 128 KB Flash
device.
Expansion ROM Base Address Register
The Expansion ROM has a memory space of 1 MB and its BAR is a Dword register that supports a
128 KB memory via the 82551ER local bus. The Expansion ROM BAR can be disabled by setting
the Boot Disable bit located in the EEPROM (word Ah, bit 11). If the Boot Disable bit is set, the
82551ER returns a 0b for all bits in this address register, avoiding request of memory allocation for
this space.
Base Address Registry Summary
The preceding description of the Base Address Registers’ functions are listed in
PCI Subsystem Vendor ID and Subsystem ID Registers
The Subsystem Vendor ID field identifies the vendor of an 82551ER based solution. The
Subsystem Vendor ID values are based upon the vendor’s PCI Vendor ID and is controlled by the
PCI Special Interest Group (SIG).
The Subsystem ID field identifies the 82551ER based specific solution implemented by the vendor
indicated in the Subsystem Vendor ID field.
Table 15. Base Address Register Functions
Register Name
Expansion BAR
BAR0
BAR1
BAR2
PCI Function
Memory CSR
BootROM
I/O CSR
Flash
PCI Window
128 KB
1 MB
4 KB
4 KB
Networking Silicon — 82551ER
Table
15.
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