Datasheet

DS1996
8 of 19
MEMORY FUNCTION EXAMPLES
Example: Write two data bytes to memory locations 0026h and 0027h (the seventh and 8th bytes of page
1). Read entire memory.
MASTER MODE
DATA (LSB FIRST)
COMMENTS
TX
Reset
Reset pulse (480-960 µs)
RX
Presence
Presence pulse
TX
CCh
Issue “skip ROM” command
TX
0Fh
Issue “write scratchpad” command
TX
26h
TA1, beginning offset=6
TX
00h
TA2, address=0026h
TX
<2 data bytes>
Write 2 bytes of data to scratchpad
TX
Reset
Reset pulse
RX
Presence
Presence pulse
TX
CCh
Issue “skip ROM” command
TX
AAh
Issue “read scratchpad” command
RX 26h Read TA1, beginning offset=6
RX
00h
Read TA2, address=0026h
RX
07h
Read E/S, ending offset=7, flags=0
RX
<2 data bytes>
Read scratchpad data and verify
TX
Reset
Reset pulse
RX
Presence
Presence pulse
TX
CCh
Issue “skip ROM” command
TX
55h
Issue “copy scratchpad” command
TX
26h
TA1
TA2 AUTHORIZATION CODE
E/S
TX
00h
TX
07h
TX
Reset
Reset pulse
RX
Presence
Presence pulse
TX
CCh
Issue “skip ROM” command
TX
F0h
Issue “read memory” command
TX
00h
TA1, beginning offset=0
TX
00h
TA2, address=0000h
RX
<8192 bytes>
Read entire memory
TX
Reset
Reset pulse
RX
Presence
Presence pulse, done