DS1864 Datasheet, PDF (24/72 Pages) Dallas Semiconductor – SFP Laser Controller and Diagnostic IC

SFP Laser Controller and
Diagnostic IC
I²C ADDRESS A0h
00h
GBIC EEPROM
(256 BYTES)
FFh
I²C ADDRESS A2h (DEFAULT)
00h
LOWER MEMORY
PASSWORD ENTRY (PWE)
(4 BYTES)
TABLE SELECT BYTE 7Fh
NOTE 1:
WHEN MODE BIT (TABLE 04h BYTE 89h BIT 3) = 0,
THE DS1864 IS IN DS1852/DS1856-COMPATIBLE CONFIGURATION (DEFAULT).
NOTE 2:
IF ADFIX = 0, THEN THE MAIN DEVICE I²C SLAVE ADDRESS IS A2h.
F ADFIX = 1, THEN THE MAIN DEVICE I²C SLAVE ADDRESS IS
DETERMINED BY THE VALUE IN 8Ch TABLE 04h (IN DS1852 CONFIGURATION).
NOTE 3:
TABLE 00h DOES NOT EXIST IN DS1852/DS1856 CONFIGURATION.
80h
TABLE 01h
80h
TABLE 02h
80h
TABLE 03h
80h
TABLE 04h
C0h
TABLE 05h
EEPROM
(120 BYTES)
F7h
F8h
EEPROM
(8 BYTES)
FFh
DAC0
LOOKUP TABLE
(72 BYTES)
C7h
DAC1
LOOKUP TABLE
(72 BYTES)
C7h
NON LOOKUP
TABLE CONTROL
AND CONFIGURATION
REGISTERS
DFh
CONTROL
AND CONFIGURATION
FBh
Figure 16. DS1852/DS1856-Compatible Configuration (Mode Bit = 0, Default)
EEPROM Write Disable
The SEE control bit resides in Table 04h (Table 01h in
DS1859 configuration), register 80h, bit 2. By default
(SEE bit = 0) these locations act as ordinary EEPROM.
By setting SEE = 1, these locations function as SRAM
memory allowing an infinite number of write cycles. This
also eliminates the requirement for the EEPROM write
time. Because changes made with SEE = 1 do not
effect the EEPROM, these changes will not be retained
through power cycles. The power-up value will be the
last value written with SEE = 0.
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