Rainbow Electronics DS1854 - Manual (Page 21)

the DS1854, the device-select bits must match one
of two valid device addresses, 00h or the address
registered in Table 01 location 8Ch. The last bit of
the command/control byte (R/W) defines the opera-
tion to be performed. When set to a ‘1’ a read opera-
tion is selected, and when set to a ‘0’ a write
operation is selected. The slave address can be set
by the EEPROM.
Following the start condition, the DS1854 monitors the
SDA bus checking the device type identifier being
transmitted. Upon receiving the 1010 control code, the
appropriate device address bits, and the read/write bit,
the slave device outputs an acknowledge signal on the
SDA line.
Chip Topology
TRANSISTOR COUNT: 44419
SUBSTRATE CONNECTED TO GROUND
DS1854
Dual Temperature-Controlled Resistors with
Two Monitors
____________________________________________________________________ 21
STOP
CONDITION
OR REPEATED
START
CONDITION
REPEATED IF MORE BYTES
ARE TRANSFERRED
ACK
START
CONDITION
ACK
ACKNOWLEDGEMENT
SIGNAL FROM RECEIVER
ACKNOWLEDGEMENT
SIGNAL FROM RECEIVER
SLAVE ADDRESS
MSB
SCL
SDA
R/W
DIRECTION
BIT
1 2 6 7 8 9 1 2 8 9 3–7
Figure 5. 2-Wire Data Transfer Protocol