DS1972 Maxim, DS1972 Datasheet - Page 11

• Manufacturer Part Number: DS1972
• Description: The DS1972 is a 1024-bit, 1-Wire® EEPROM chip organized as four memory pages of 256 bits each in a rugged iButton® package
• Manufacturer: Maxim

Figure 7b. Memory Function Flowchart (continued)
FROM FIGURE 7a
TO FIGURE 7a
TA1 (T[7:0]), TA2 (T[15:8])
COPY SCRATCHPAD?
MASTER Tx RESET?
BUS MASTER Tx
AND E/S BYTE
BUS MASTER
AUTH. CODE
MATCH?
Rx "1"s
N
55h
______________________________________________________________________________________
Y
Y
N
Y
N
DURATION: t
APPLICABLE TO ALL R/W
MEMORY LOCATIONS.
T[15:0] < 0090h?
N
PROG
N
Y
Y
* 1-Wire IDLE HIGH FOR POWER.
COPY PROTECTED?
MASTER Tx RESET?
MASTER Tx RESET?
DATA TO ADDRESS
DS1972 COPIES
SCRATCHPAD
DS1972 Tx "0"
DS1972 Tx "1"
PF = 0?
Y
AA = 1
Y
N
N
Y
TA1 (T[7:0]), TA2 (T[15:8])
1024-Bit EEPROM iButton
READ MEMORY?
ADDRESS < 90h?
BUS MASTER Tx
*
N
N
F0h
Y
INCREMENTS
BUS MASTER
ADDRESS
COUNTER
DS1972
Rx "1"s
N
Y
Y
N
DS1972 SETS MEMORY
ADDRESS = (T[15:0])
MEMORY ADDRESS
MASTER Tx RESET?
MASTER Tx RESET?
DATA BYTE FROM
ADDRESS < 8Fh?
BUS MASTER Rx
N
N
Y
Y
N
MASTER Tx RESET?
BUS MASTER
Rx "1"s
Y
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