Datasheet

DS2408
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Command-Specific 1-Wire Communication Protocol—Legend
SYMBOL DESCRIPTION
RST 1-Wire Reset Pulse generated by master.
PD 1-Wire Presence Pulse generated by slave.
Select Command and data to satisfy the ROM function protocol.
RPR Command "Read PIO Registers".
CAR Command "Channel-Access Read".
CAW Command "Channel-Access Write".
WCS Command "Write Conditional Search Register".
RAL Command "Reset Activity Latches".
TA Target Address TA1, TA2.
<data> Transfer of an undetermined amount of data.
CRC16\ Transfer of an inverted CRC16.
FF loop Indefinite loop where the master reads FF bytes.
AA loop Indefinite loop where the master reads AA bytes.
<32 samples>,
CRC16\ loop
Indefinite loop where the master reads 32 PIO samples followed by an inverted CRC16.
<new state>, <new
state\>
Transfer of 2 bytes, where the second byte is the bit-inverse of the first byte. The first
byte will be taken as the new PIO state.
AAh, <read back>
Transfer of 2 bytes, where the first byte is a constant (AAh) and the second byte is the
current PIO state.
<new state>,
<invalid>
Transfer of 2 bytes, where the second byte is NOT the bit-inverse of the first byte.
Command-Specific 1-Wire Communication Protocol—Color Codes
Master to slave Slave to master
Read PIO Registers (Success)
RST PD Select RPR TA <data> CRC16\ FF loop
Read PIO Registers (Fail Address)
RST PD Select RPR TA FF loop
Channel-Access Read (Cannot Fail)
RST PD Select CAR <32 samples>, CRC16\ loop