Rainbow Electronics DS2422 - Manual (Page 35)

DS2422
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bus performs a reset. The DS2422 will communicate properly when used in conjunction with a DS2480B or
DS2490 1-Wire driver and adapters that are based on these driver chips.
Figure 13. Hardware Configuration
Open Drain
Port Pin
RX = RECEIVE
TX = TRANSMIT
100 W
MOSFET
V
PUP
RX
TX
TX
RX DATA
R
PUP
5 µA
Typ.
BUS MASTER DS2422 1-Wire PORT
TRANSACTION SEQUENCE
The protocol for accessing the DS2422 through the 1-Wire port is as follows:
§ Initialization
§ ROM Function Command
§ Memory/Control Function Command
§ Transaction/Data
INITIALIZATION
All transactions on the 1-Wire bus begin with an initialization sequence. The initialization sequence consists of a
reset pulse transmitted by the bus master followed by presence pulse(s) transmitted by the slave(s). The presence
pulse lets the bus master know that the DS2422 is on the bus and is ready to operate. For more details, see the
1-Wire Signaling section.