LSI LSI53C896, Technical Manual

Page: 124 / 370

4-12 Registers
Registers: 0x2E–0x2F
Subsystem ID
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 will
contain the value downloaded from the serial EEPROM
or a value of 0x0000 if the download fails.
If the external serial EEPROM is disabled (MAD[7] pulled
HIGH), the register returns a value of 0x1000. The 16-bit
value that should be stored in the external serial
EEPROM is vendor specific. Please see
Section 2.4,
“Serial EEPROM Interface,” for additional information on
downloading a value for this register.
Registers: 0x30–0x33
Expansion ROM Base Address
Read/Write
ERBA Expansion ROM Base Address [31:0]
This four-byte register handles the base address and size
information for the expansion ROM. It functions exactly
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
31 0
ERBA
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1
*