CS8900A
Crystal LAN™ ISA Ethernet Controller
4.3 Bus Interface Registers
4.3.1 Product Identification Code
(Read only, Address: PacketPage base + 0000h)
Address 0000h
First byte of EISA registration
number for
Adress 0001h
Second byte of EISA
registration number for Crys-
tal Semiconductor
Address 0002h
Address 00003h
Last 3 bits of the Product ID
number (5 “X” bits are the revi-
sion number)
First 8 bits of
Product ID number
Crystal Semiconductor
The Product Identification Code Register is located in the first four bytes of the PacketPage (0000h to 0003h). The
register contains a unique 32-bit product ID code that identifies the chip as a CS8900A. The host can use this num-
ber to determine which software driver to load and to check which features are available.
Reset value is: 0000 1110 0110 0011 0000 0000 000X XXXX
The X XXXX codes for the CS8900A are:
Rev B: 0 0111
4.3.2 I/O Base Address
(Read/Write, Address: PacketPage base + 0020h)
Address 0021h
Address 0020h
Most significant byte of I/O Base Address
Least significant byte of I/O Base Address
The I/O Base Address Register describes the base address for the sixteen contiguous locations in the host system’s
I/O space, which are used to access the PacketPage registers. See Section 4.10 on page 76. The default location
is 0300h.
After reset, if no EEPROM is found by the CS8900A, then the register has the following initial state. If an EEPROM
is found, then the register’s initial value may be set by the EEPROM. See Section 3.3 on page 19.
Reset value is: 0000 0011 0000 0000
CIRRUS LOGIC PRODUCT DATA SHEET
42
DS271PP3
CIRRUS [ CIRRUS LOGIC ]
