DS1922E Maxim, DS1922E Datasheet - Page 9

• Manufacturer Part Number: DS1922E
• Description: The DS1922E temperature logger iButton is a rugged, self-sufficient system that measures temperature and records the result in a protected memory section
• Manufacturer: Maxim

Figure 5 shows the DS1922E memory map. Pages 0 to
15 contain 512 bytes of general-purpose SRAM. The
various registers to set up and control the device fill
pages 16 and 17, called register pages 1 and 2 (see
Figure 6 for details). Pages 18 and 19 can be used as
extension of the general-purpose memory. The data-log
logging memory starts at address 1000h (page 128)
and extends over 256 pages. The memory pages 20 to
127 are reserved for future extensions. The scratchpad
is an additional page that acts as a buffer when writing
to the SRAM memory or the register page. The data
Figure 5. Memory Map
High-Temperature Logger iButton with 8KB
_______________________________________________________________________________________
0000h TO 001Fh
0020h TO 01FFh
0200h TO 021Fh
0220h TO 023Fh
0240h TO 025Fh
0260h TO 027Fh
0280h TO 0FFFh
1000h TO 2FFFh
ADDRESS
(RESERVED FOR FUTURE EXTENSIONS)
32-BYTE GENERAL-PURPOSE SRAM
32-BYTE INTERMEDIATE STORAGE
DATA-LOG MEMORY (READ ONLY)
GENERAL-PURPOSE SRAM (R/W)
GENERAL-PURPOSE SRAM (R/W)
GENERAL-PURPOSE SRAM (R/W)
32-BYTE REGISTER PAGE 1
32-BYTE REGISTER PAGE 2
Memory
SCRATCHPAD
(R/W)
memory can be written at any time. The access type for
the register pages is register-specific and depends on
whether the device is programmed for a mission.
Figure 6 shows the details. The data-log memory is
read only for the user. It is written solely under supervi-
sion of the on-chip control logic. Due to the special
behavior of the write access logic (write scratchpad,
copy scratchpad), it is recommended to only write full
pages at a time. This also applies to the register pages.
See the Address Registers and Transfer Status section
for details.
Data-Log Memory
PAGES 128 TO 383
PAGES 20 TO 127
PAGES 1 TO 15
PAGE 16
PAGE 17
PAGE 18
PAGE 19
PAGE 0
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