User Manual

DS1678
22 of 26
2-WIRE SERIAL COMMUNICATION WITH DS1678 Figure 4
A2
10W 0
A
0W1S 1 0 A1 A000 A A P
SDA
SCL
Device Address Byte Memory Address ByteStart
DS1678
ACK
Stop
DS1678
ACK
Write to Memory Address Pointer
1S 1 1000 Rd A N P
SDA
SCL
Device Address Byte Data ByteStart
DS1678
ACK
StopMaster
NACK
Read Single Byte from Current Memory Address Pointer Location
D1D2D3D4D5D6D70 D0
1S 1 10 D000 Rd A A
SDA
SCL
Device Address Byte Most Significant
Data Byte
Start
DS1678
ACK
Master
ACK
Read Multiple Bytes from Current Memory Address Pointer Location
D1D2D3D4D5D6D7 NP
StopMaster
NACK
Least Significant
Data Byte
D1D2D3D4D5D6D70 D0
1S 1 000 A A
SDA
SCL
Device Address Byte Memory Address ByteStart
DS1678
ACK
DS1678
ACK
Read Single Byte from New Memory Address Pointer Location
1R 1 1000 Rd A
Device Address
Byte
Repeated
Start
DS1678
ACK
NP
Data Byte StopMaster
NACK
D1D2D3D4D5D6 D0
SDA
SCL
D7
SDA
SCL
Write to Memory Location (Single Byte)
AP
Stop
DS1678
ACK
D0
Data Byte
D1D2D3D4D5D6D7
A3A4A5A6A7
0W
1S 1 0 A1 A000 A
Device Address Byte Memory Address ByteStart
DS1678
ACK
DS1678
ACK
A2A3A4A5A6A7
1
1
A1 A0
A2A3A4A5A6A7
2-WIRE COMMUNICATION TIMING DIAGRAM Figure 5
SU:STO
t
HD:STA
t
t
SU:STA
SU:DAT
t
t
HIGH
R
t
t
LOW
t
HD:STA
SCL
START
SDA
STOP
t
BUF
t
F
REPEATED
S
TART
t
HD:DAT