Serial Identification (EEPROM)
The SFP 2‐wire serial interface (MOD_DEF1/MOD_DEF2) provides access to the
identification information describing SFP capabilities, interfaces, and associated
information. The serial interface uses the 2‐wire serial EEPROM protocol defined
for the ATMEL AT24C02 family component. The memory is organized as a series
of 8‐bit data words that can be addressed individually or sequentially. The
content of the SERIAL IDENTIFICATION (serial ID) device is write‐protected. The
2‐wire serial bus address 1010000X (A0h) is used for serial ID access.
The table below defines the information structures that are obtained from the
SFP Transceiver via the serial ID.
Table 2: Serial Identification Registers
Addr
Registry Name
Registry Description
Value
BASE ID FIELDS
0
Identifier
Type of serial transceiver
Vendor specific – Video transceiver MSA
80h
1
Ext. Identifier
Extended type of serial transceiver
SFP function is defined by serial ID only
04h
2
Connector
Connector type
Vendor specific ‐ HD‐BNC
82h
3
Transceiver
Electronic or optical compatibility
SMPTE 259M, 344M, 292M, 424M
82h
4
Reserved
MSA do not specify any SMPTE standard code
00h
5
00h
6
00h
7
00h
8
00h
9
00h
10
00h
11
Encoding
Code for serial encoding algorithm
Unallocated ‐ NRZI
07h
12
BR, Nominal
Nominal bit rate, units of 100Mbps
3Gbps
1Eh
13
Reserved
Reserved
00h
14
Reserved
Reserved
Fiber Not Supported
00h
15
00h
16
00h
17
00h
18
Length (Copper)
Length supported (cooper) in m
255m (Vary with bit rate)
FFh
19
Reserved
Reserved
00h
20
Vendor name SFP transceiver vendor name (ASCII)
“FIBERPLEX”
46h
21
49h
22
42h
23
45h
24
52h
25
50h
26
4Ch
27
45h
28
58h
29
20h
30
20h
31
20h
32
20h
33
20h
0
95
127
Serial ID defined by
SFP MSA
(96 bytes)
Two wire Address A0h (10100000Xb)
Vendor specific
(32 bytes)
Figure 5 EEPROM memory mapping
