DS18B20-SL DALLAS [Dallas Semiconductor], DS18B20-SL Datasheet - Page 13

• Manufacturer Part Number: DS18B20-SL
• Description: Programmable Resolution 1-Wire Digital Thermometer
• Manufacturer: DALLAS [Dallas Semiconductor]

Figure 11. ROM Commands Flowchart
SERIAL NUMBER
FAMILY CODE
DS18B20 T
DS18B20 T
DS18B20 T
READ ROM
CRC BYTE
COMMAND
6 BYTES
1 BYTE
33h
Y
X
X
X
Initialization
Sequence
N
MATCH ROM
MASTER T
MASTER T
MASTER T
COMMAND
MATCH?
MATCH?
MATCH?
BIT 63
BIT 0
BIT 0
BIT 1
BIT 63
BIT 1
55h
Y
Y
Y
Y
MASTER T
X
RESET PULSE
X
X
DS18B20 T
PRESENCE
MASTER T
COMMAND
N
PULSE
N
N
N
X
ROM
X
X
(FIGURE 12)
MASTER T
FUNCTION
COMMAND
N
N
N
DS18B20 T
DS18B20 T
MASTER T
DS18B20 T
DS18B20 T
MASTER T
DS18B20 T
DS18B20 T
MASTER T
SEARCH ROM
COMMAND
13 of 22
MATCH?
MATCH?
Y
Y
MATCH?
BIT 0
BIT 1
BIT 63
X
F0h
X
X
X
X
X
X
Y
X
X
X
Y
BIT 63
BIT 63
BIT 0
BIT 0
BIT 0
BIT 63
BIT 1
BIT 1
BIT 1
N
DS18B20 T
DS18B20 T
MASTER T
ALARM SEARCH
WITH ALARM
COMMAND
FLAG SET?
DEVICE(S)
ECh
X
X
X
Y
Y
BIT 0
BIT 0
BIT 0
N
N
COMMAND
SKIP ROM
CCh
Y
N
DS18B20