Obtaining ieee addresses, An83 – Cirrus Logic AN83 User Manual
Page 55

AN83
AN83REV3
55
ture storing the Driver Configuration Block in
BIOS space.
OBTAINING IEEE ADDRESSES
Each node of a Local Area Network has a unique
address for the media access control (MAC). This
makes it possible for that particular node to have
unique identity for data communication. This ad-
dress, known as the IEEE physical address, con-
sists of 48 bits of data. This address is assigned to
a LAN physical interface node by the manufacturer
of the network interface card.
To ensure uniqueness of the address, 24 bits of out
of the 48 bits of the physical address are assigned
to the manufacturer by the IEEE standards commit-
tee. This 24 bit address is known as Organization-
ally Unique Identifier (OUI). The remaining 24
bits of the address are assigned by the manufactur-
er. For further information and an application for
an OUI, please contact the IEEE at the following
address:
IEEE Registration Authority,
IEEE Standards Department,
445 Hoes Lane, PO Box 1331
Piscataway, NJ 08855-1331, USA
Telephone: (732) 562-3813
FAX: (732) 562-1571
Email: [email protected]
http://standards.ieee.org/regauth/oui/index.shtml
Adapter boards shipped as part of Cirrus’
CS8900A Evaluation Kit are programmed with an
IEEE Physical Address obtained from an allotment
assigned to Cirrus Logic by the IEEE.
Byte Offset
Description
Function
00h
Header
8 bytes = “$CS89XX$”
08h
Individual Address
IEEE individual address. Same format as word 1Ch in Table 8
0Ah
Individual Address
IEEE individual address. Same format as word 1Dh in Table 8
0Ch
Individual Address
IEEE individual address. Same format as word 1Eh in Table 8
0Eh
ISA Configuration Flags
Same format as word 1Fh in Table 8
10h
Packet Page Base
12 MSBs of 24-bit address (lower 12 bits assumed = 0)
12h
Boot PROM Base
12 MSBs of 24-bit address (lower 12 bits assumed = 0)
14h
Boot PROM Mask
12 MSBs of 24-bit addr mask (lower 12 bits assumed = 0)
16h
Transmission Control
Same format as word 23h in Table 8
18h
Adapter Configuration
Same format as word 24h in Table 8
1Ah
EEPROM Revision
Same format as word 25h in Table 8
1Ch
Reserved
Reserved for future use, set to 0
1Eh
Mfg Date
Same format as word 27h in Table 8
20h-25h
IEEE Individual Addr
Copy of 6 bytes at offset 08h
26h
Reserved
Reserved for future use, set to 0
28h
Reserved
Reserved for future use, set to 0
2Ah
Reserved
Reserved for future use, set to 0
2Ch
Reserved
Reserved for future use, set to 0
2Eh
Checksum
Word-wide checksum of words 08h to 2Fh (zero sum)
30h
EISA ID (high word)
Same format as word 30h in Table 8
32h
EISA ID (low word)
Same format as word 31h in Table 8
34h
Serial Number
Same format as word 32h in Table 8
36h
Serial Number
Same format as word 33h in Table 8
38h
LDSR Checksum
Same format as word 34h in Table 8
Table 9. Format of Driver Configuration Block in BIOS space