DS1921H-F5# Maxim Integrated Products, DS1921H-F5# Datasheet - Page 6

• Manufacturer Part Number: DS1921H-F5#
• Description: IBUTTON THERMOCHRON F5
• Manufacturer: Maxim Integrated Products
• Series: iButton®r

Specifications of DS1921H-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

DS1921H/Z REGISTER PAGE MAP Figure 6
*The first entry in column ACCESS is valid between missions. The second entry shows the applicable
access mode while a mission is in progress.
**While a mission is in progress, these addresses can be read. The first attempt to write to these registers
(even read-only ones), however, will end the mission and overwrite selected writeable registers.
TIMEKEEPING
The RTC/alarm and calendar information is accessed by reading/writing the appropriate bytes in the
register page, address 200h to 206h. Note that some bits are set to 0. These bits will always read 0
regardless of how they are written. The contents of the time, calendar, and alarm registers are in the
Binary-Coded Decimal (BCD) format.
020Ch
020Dh
021Ch
021Dh
ADDR
020Ah
020Bh
020Eh
020Fh
021Ah
021Bh
021Eh
021Fh
0200h
0201h
0202h
0203h
0204h
0205h
0206h
0207h
0208h
0209h
0210h
0211h
0212h
0213h
0214h
0215h
0216h
0217h
0218h
0219h
CENT
EOSC
TCB
MM
MS
MH
MD
b7
0
0
0
0
0
Number of Minutes Between Temperature Conversions
EMCLR
MEMCLR
12/24
12/24
b6
0
0
0
0
10 Years
10 Seconds Alarm
10 Minutes Alarm
Temperature Read Out (Forced Conversion)
10 Seconds
10 Minutes
AM/PM
Temperature High Alarm Threshold
Temperature Low Alarm Threshold
10ha.
20h.
MIP
A/P
b5
0
0
0
0
10 Date
(no function, reads 00h)
(no function, reads 00h)
10m.
10h.
10h.
alm.
SIP
EM
b4
Center Byte
Center Byte
0
0
High Byte
High Byte
High Byte
Low Byte
Low Byte
Low Byte
Minutes
Month
Hours
Date
Year
RO
b3
0
0
0
6 of 45
Single Seconds Alarm
Single Minutes Alarm
Single Hours Alarm
Single Seconds
Single Minutes
Single Months
TLS
TLF
Single Hours
Single Years
b2
Single Date
Day of Week Alarm
Day of Week
THS
THF
b1
TAS
TAF
b0
Function
Registers
Registers
Samples
Samples
Counter
Counter
Mission
Mission
Control
Alarms
Sample
Device
Stamp
Temp.
Temp.
Status
Alarm
Delay
Real-
Clock
Real-
Clock
(N/A)
(N/A)
Time
Time
Time
Start
Rate
R/W; R/W
R/W; R/W**
R/W; R/W**
R/W; R/W**
R/W; R/W**
R/W; R/W**
R/W; R**
Access*
DS1921H/Z
R; R**
R; R**
R; R**
R; R
R; R
R; R