Ds1875 pon triplexer and sfp controller – Rainbow Electronics DS1875 User Manual
Page 56
DS1875
PON Triplexer and SFP Controller
56
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Lower Memory, Register 7Bh to 7Eh: Password Entry (PWE)
POWER-ON
VALUE
FFFF
FFFFh
READ
ACCESS N/A
WRITE
ACCESS All
MEMORY
TYPE Volatile
7Bh 2
31
2
30
2
29
2
28
2
27
2
26
2
25
2
24
7Ch 2
23
2
22
2
21
2
20
2
19
2
18
2
17
2
16
7Dh 2
15
2
14
2
13
2
12
2
11
2
10
2
9
2
8
7Eh 2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
BIT
7
BIT
0
There are two passwords for the DS1875. Each password is 4 bytes long. The lower level password (PW1) has all the
access of a normal user plus those made available with PW1. The higher level password (PW2) has all the access of
PW1 plus those made available with PW2. The values of the passwords reside in EEPROM inside PW2 memory. At
power-up, all PWE bits are set to 1. All reads at this location are 0.
Lower Memory, Register 7Fh: Table Select (TBL SEL)
POWER-ON
VALUE
00h
READ
ACCESS All
WRITE
ACCESS All
MEMORY
TYPE Volatile
7Fh 2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
BIT
7
BIT
0
The upper memory tables (Table 00h to 08h) of the DS1875 are accessible by writing the desired table value in this
register.