Datasheet

DS1720
9 of 14
DS1720 COMMAND SET Table 3
INSTRUCTION DESCRIPTION PROTOCOL
3-WIRE BUS
DATA AFTER
ISSUING
PROTOCOL NOTES
TEMPERATURE CONVERSION COMMANDS
Read Temperature Temperature Reads last converted
temperature value from
temperature register
AAh <read data>
Read Counter Reads value of count remaining
from counter
A0h <read data>
Read Slope Reads value of the slope
accumulator
A9h <read data>
Start Convert T Initiates temperature conversion EEh Idle 1
Stop Convert T Halts temperature conversion 22h Idle 1
THERMOSTAT COMMANDS
Write T
H
Writes high temperature limit
value into T
H
register
01h <write data> 2
Write T
L
Writes low temperature limit value
into T
L
register
02h <write data> 2
Read T
H
Reads stored value of high
temperature limit from T
H
register
A1h <read data> 2
Read T
L
Reads stored value of low
temperature limit from T
L
register
A2h <read data> 2
Write Config Writes configuration data to
configuration register
0Ch <write data> 2
Read Config Reads configuration data from
configuration register
ACh <read data> 2
NOTES:
1. In continuous conversion mode, a Stop Convert T command will halt continuous conversion. To
restart, the Start Convert T command must be issued. In one–shot mode, a Start Convert T command
must be issued for every temperature reading desired.
2. Writing to the E
2
typically requires 10 ms at room temperature. After issuing a write command, no
further writes should be requested for at least 10 ms.