Datasheet

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4.0 Register Set (Continued)
DP83815
4.1.6 Configuration Memory Address Register
This register specifies the Base Memory address which is required to build an address map during configuration. It also
specifies the number of bytes required as well as an indication that it can be mapped into memory space.
4.1.7 Configuration Subsystem Identification Register
The CFGSID allows system software to distinguish between different subsystems based on the same PCI silicon. The
values in this register can be loaded from the EEPROM if configuration is enabled.
Tag: CFGMA Size: 32 bits Hard Reset: 00000000h
Offset: 14h Access: Read Write Soft Reset: unchanged
Bit Bit Name Description
31-12 MEMBASE Memory Base Address
This is set by software to the base address for the Operational Register Map.
11-4 MEMSIZE Memory Size
These bits return 0, which indicates that the DP83815 requires 4096 bytes of Memory Space (the
minimum recommended allocation).
3 MEMPF Prefetchable
Set to 0 by DP83815. Read Only.
2-1 MEMLOC Location Selection
Set to 00 by DP83815. This indicates that the base register is 32-bits wide and can be placed anywhere
in the 32-bit memory space. Read Only.
0 MEMIND Memory Space Indicator
Set to 0 by DP83815 to indicate that DP83815 is capable of being mapped into memory space. Read
Only.
Tag: CFGSID Size: 32 bits Hard Reset: 00000000h
Offset: 2Ch Access: Read Only Soft Reset: unchanged
Bit Bit Name Description
31-16 SDEVID Subsystem Device ID
Set to 0 by DP83815.
15-0 SVENID Subsystem Vendor ID
Set to 0 by DP83815.
Obsolete