LSI LSI53C1000, Technical Manual

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PCI Configuration Registers 4-13
If the external serial EEPROM interface is enabled
(MAD[7] LOW), this register is automatically loaded at
power-up from the external serial EEPROM and contains
the value downloaded from the serial EEPROM or, if the
download fails, a value of 0x0000.
If the external serial EEPROM interface is disabled
(MAD[7] HIGH), this register returns a value of 0x1000.
The 16-bit value that should be stored in the external
serial EEPROM for this register is the vendor’s PCI
Vendor ID. This value must be obtained from the PCI
Special Interest Group (SIG). Please see
Section 2.4,
“Serial EEPROM Interface,” for more information on
downloading a value for this register.
Registers: 0x2E–0x2F
Subsystem ID (SID)
Read Only
SID Subsystem ID [15:0]
This 16-bit register is used to uniquely identify the add-in
board or subsystem where this PCI device resides. It
provides a mechanism for an add-in card vendor to
distinguish its cards from one another even if the cards
have the same PCI controller installed on them (and
therefore the same Vendor ID and Device ID).
If the external serial EEPROM interface is enabled
(MAD[7] is LOW), this register is automatically loaded at
power-up from the external serial EEPROM and contains
the value downloaded from the serial EEPROM or, if the
download fails, a value of 0x0000.
If the external serial EEPROM is disabled (MAD[7] pulled
HIGH), the register returns a value of 0x1000. The 16-bit
value stored in the external serial EEPROM is
15 0
SID
If MAD[7] is HIGH
0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0
If MAD[7] is LOW
x x x x x x x x x x x x x x x x