DS1921 DALLAS [Dallas Semiconductor], DS1921 Datasheet - Page 34

• Manufacturer Part Number: DS1921
• Description: High-Resolution Thermochron iButton
• Manufacturer: DALLAS [Dallas Semiconductor]

Command-Specific 1-Wire Communication Protocol — Color Codes
Write Scratchpad, reaching the end of the Scratchpad
Write Scratchpad, not reaching the end of the Scratchpad
Read Scratchpad
Copy Scratchpad (success)
Copy Scratchpad (invalid TA-E/S)
Read Memory (success)
Read Memory (invalid address)
Reading reserved pages 20 through 63 or 68 through 127 or pages 192 and higher (beyond datalog
memory) will result in 00h bytes.
Read Memory with CRC (success)
The "32 bytes" are either valid page data or 00h bytes when reading reserved pages 20 through 63 or 68
through 127 or pages 192 and higher (beyond datalog memory).
Master to slave
RST
RST
RST
RST
RST
RST
RST
RST
PD
PD
PD
PD
PD
PD
PD
PD
Select
Select
Select
Select
Select
Select
Select
Select
Slave to master
WS
WS
RS
CPS
CPS
RM
RM
RMC
TA-E/S
TA
TA
TA
TA
TA-E/S
TA-E/S
TA
00 loop
<data to EOM>
<data to EOS>
<data>
<data to EOP>
<data to EOS>
AA loop
FF loop
RST
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00 loop
CRC16\
PD
CRC16\
CRC16\
FF loop
<32 bytes>
FF loop
Loop
CRC16\
DS1921H/Z