page 32
DS1820 is a digital temperature
sensor that uses
1-wire®
interface
for it’s operation. It is
capable of measuring temperatures
within the range of -55 to 128°C,
and provides ±0.5°C accuracy for
temperatures within the range of -10 to
85°C. It requires 3V to 5.5V power supply
for stable operation. It takes maximum
of 750ms for the DS1820 to calculate
temperature with 9-bit resolution.
1-wire® serial communication
enables
data to be transferred over a single
communication line, while the process
itself is under the control of the master
microcontroller. The advantage of
such communication is that only one
microcontroller pin is used. Multiple
sensors can be connected on the same
line. All slave devices by default have
a unique ID code, which enables the
master device to easily identify all
devices sharing the same interface.
Board provides a separate so cket (
TS1
)
for the DS1820. Communica tion line
with the microcontroller is selected with
a
J3
jumper.
DS1820 - Digital
Temperature Sensor
D
AT
A BUS
R4
G1.7
G2.0
VCC-3.3V
mikromedia
™
workStation v7 enables you to establish 1-wire® communication
between
DS1820
and the microcontroller over
G1.7
or
G2.0
pins. The selecti on
of either of those two lines is done using
J3
jumper. When placing the sensor in
the socket make sure that half-circle on the board’s silkscreen markings matches
the rounded part of the DS1820 sensor. If you accidentally connect the sensor
the other way, it may be permanently damaged. Make sure to disconnect other
peripherals (except those in 1-wire network), LEDs and additional pull-up or pull-
down resistors from the interface lines in order not to interfere with signal/data
integrity.
Figure 12-1:
DS1820 not
connected
Figure 12-2:
DS1820
placed in
socket
Figure 12-3:
DS1820
connected
to G1.7 pin
Figure 12-4:
DS1820
connected
to G2.0 pin
Figure 12-5: DS1820 connected to G2.0 pin
Enabling DS1820 Sensor
1
2
3
4
other modules
