DS18B20-PAR_07 MAXIM [Maxim Integrated Products], DS18B20-PAR_07 Datasheet - Page 10

• Manufacturer Part Number: DS18B20-PAR_07
• Description: 1-Wire Parasite-Power Digital Thermometer
• Manufacturer: MAXIM [Maxim Integrated Products]

transmitted least significant bit first. All three bytes MUST be written before the master issues a reset, or
the data may be corrupted.
READ SCRATCHPAD [BEh]
This command allows the master to read the contents of the scratchpad. The data transfer starts with the
least significant bit of byte 0 and continues through the scratchpad until the 9
read. If only part of the scratchpad contents is required, the master may issue a reset to terminate reading
at any time.
COPY SCRATCHPAD [48h]
This command copies the contents of the scratchpad T
to EEPROM. Within 10 μs (max) after this command is issued the master must enable a strong pullup on
the 1-Wire bus for at least 10 ms as described in the PARASITE POWER section.
RECALL E
This command recalls the alarm trigger values (T
places the data in bytes 2, 3, and 4, respectively, in the scratchpad memory. The master device can issue
“read time slots” (see the 1-WIRE BUS SYSTEM section) following the Recall E
DS18B20-PAR will indicate the status of the recall by transmitting 0 while the recall is in progress and
1 when the recall is done. The recall operation happens automatically at power-up, so valid data is
available in the scratchpad as soon as power is applied to the device.
DS18B20-PAR Function Command Set Table 4
NOTES:
1. The master must enable a strong pullup on the 1-Wire bus during temperature conversions and copies
2. The master can interrupt the transmission of data at any time by issuing a reset.
3. All three bytes must be written before a reset is issued.
Convert T
Read Scratchpad
Write Scratchpad
Copy Scratchpad
Recall E
from the scratchpad to EEPROM. No other bus activity may take place during this time.
Command
2
2
[B8h]
Initiates temperature
conversion.
Reads the entire scratchpad
including the CRC byte.
Writes data into scratchpad
bytes 2, 3, and 4 (T
configuration registers).
Copies T
configuration register data from
the scratchpad to EEPROM.
Recalls T
configuration register data from
EEPROM to the scratchpad.
TEMPERATURE CONVERSION COMMANDS
H
H
Description
, T
, T
L
L
, and
, and
MEMORY COMMANDS
H
, T
L
, and
10 of 19
H
and T
H
, T
Protocol
L
L
BEh
B8h
4Eh
44h
48h
) and configuration data from EEPROM and
and configuration registers (bytes 2, 3 and 4)
DS18B20-PAR transmits up
After Command is Issued
DS18B20-PAR transmits
to 9 data bytes to master.
bytes to DS18B20-PAR.
Master transmits 3 data
recall status to master.
1-Wire Bus Activity
th
None
None
byte (byte 8 – CRC) is
2
command and the
DS18B20-PAR
Notes
1
2
3
1