Datasheet

DS1683
Total-Elapsed-Time and Event Recorder with Alarm
12Maxim Integrated
REGISTERS 02h–05h: PASSWORD ENTRY (PWE)
REGISTERS 08h–09h: EVENT COUNTER REGISTER
Factory Default FF FF FF FFh
Read Access N/A; Reads as all 0s
Write Access All
Memory Type SRAM, Volatile
Memory
Access
R/W R/W R/W R/W R/W R/W R/W R/W
02h 2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
03h 2
15
2
14
2
13
2
12
2
11
2
10
2
9
2
8
04h 2
23
2
22
2
21
2
20
2
19
2
18
2
17
2
16
05h 2
31
2
30
2
29
2
28
2
27
2
26
2
25
2
24
BIT 7 BIT 0
There is one 4-byte password for the DS1683. Entering the correct password into the Password Entry (PWE) bytes allows write
access to the Event, ETC, Event Counter Alarm Limit, ETC Alarm Limit, Configuration, Password Value, and User Memory regis-
ters. This value is write-only, and reads from this location result in all 0s. On power-up, the PWE bits are set to 1 to match the fac-
tory default Password Value of all 1s.
Factory Default 00 00h
Read Access All
Write Access PW
Memory Type Shadowed EEPROM, Nonvolatile
Memory
Access
R/W R/W R/W R/W R/W R/W R/W R/W
08h 2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
09h 2
15
2
14
2
13
2
12
2
11
2
10
2
9
2
8
BIT 7 BIT 0
The Event Counter register is a shadowed EEPROM register that contains the number of times a falling edge of the EVENT pin
has occurred. On power-up, on every rising edge of the EVENT pin, and after an I
2
C write to the Event Counter register, the value
from the shadowed EEPROM is loaded up into the Event Counter memory (SRAM). It is this memory that is incremented on the
falling edge of the EVENT pin. On the falling edge of the EVENT pin, this value in SRAM memory is then written to the shadowed
EEPROM memory to store the number of times there has been a falling edge on the EVENT pin.