DS1922T-F5# Maxim Integrated Products, DS1922T-F5# Datasheet - Page 31

• Manufacturer Part Number: DS1922T-F5#
• Description: IBUTTON TEMP LOGGER
• Manufacturer: Maxim Integrated Products
• Series: iButton®r

Specifications of DS1922T-F5#

• Rohs Information: IButton RoHS Compliance Plan
• Memory Size: 512B
• Memory Type: NVSRAM (Non-Volatile SRAM)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Figure 9a. Memory/Control Function Flowchart
SCRATCHPAD
INCREMENTS
DS1922
OFFSET
N
Y
Y
CONTROL FUNCTION COMMAND
SCRATCHPAD OFFSET = [T4:T0]
COMMAND, ADDRESS DATA
TO SCRATCHPAD OFFSET
MASTER Tx MEMORY OR
MASTER Tx DATA BYTE
MASTER Rx CRC-16 OF
DS1922 SETS [E4:E0] =
SCRATCHPAD OFFSET
WRITE SCRATCHPAD?
AND CLEARS (PF, AA)
MASTER Tx RESET?
MASTER Tx RESET?
MASTER Tx RESET?
OFFSET = 11111b?
MASTER Rx "1"s
SCRATCHPAD
DS1922 SETS
TA2 [T15:T8]
MASTER Tx
TA1 [T7:T0]
MASTER Tx
______________________________________________________________________________________
0Fh
Y
N
Y
N
N
Temperature Logger iButton with 8KB
BYTE WRITTEN?
N
Y
PARTIAL
N
FLOWCHART (FIGURE 11)
FROM ROM FUNCTIONS
Y
PF = 1
SCRATCHPAD
INCREMENTS
DS1922
OFFSET
N
Y
SCRATCHPAD OFFSET = [T4:T0]
E/S BYTE, AND DATA STARTING
MASTER Rx DATA BYTE FROM
FLOWCHART (FIGURE 11)
COMMAND, ADDRESS DATA,
MASTER Rx ENDING OFFSET
AT THE TARGET ADDRESS
TO ROM FUNCTIONS
MASTER Rx CRC-16 OF
SCRATCHPAD OFFSET
READ SCRATCHPAD?
WITH DATA STATUS
MASTER Tx RESET?
MASTER Tx RESET?
OFFSET = 11111b?
MASTER Rx "1"s
SCRATCHPAD
DS1922 SETS
TA2 [T15:T8]
MASTER Rx
TA1 [T7:T0]
MASTER Rx
(E/S)
AAh
Y
N
Y
N
N
Y
MASTER Rx "1"s
Data-Log Memory
N
N
DS1922 COPIES SCRATCHPAD
TA1 [T7:T0], TA2 [T15:T8]
64 BITS [PASSWORD]
COPY SCRATCHPAD
MASTER Tx RESET?
MASTER Tx RESET?
DATA TO MEMORY
AUTHORIZATION
CODE MATCH?
DS1922 Tx "0"
DS1922 Tx "1"
PASSWORD
ACCEPTED?
MASTER Tx
MASTER Tx
MASTER Tx
[WITH PW]
E/S BYTE
COPYING
FINISHED
AA = 1
99h
Y
Y
Y
Y
N
Y
N
N
N
Y
MASTER Tx RESET?
MASTER Rx "1"s
AUTHORIZATION
CODE
Y
FROM FIGURE 9b
TO FIGURE 9b
N
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