Easy
PIC
for dsPIC30
®
v7
page 28
D
AT
A BUS
VCC-BRD
R17
1K
J9
RA11
RE0
DS1820 - Digital
Temperature Sensor
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 socket (TS1)
for the DS1820. Communication line
with the microcontroller is connected via
jumper J9.
EasyPIC
™
v7 for dsPIC30
®
enables you to establish 1-wire
®
communication between
DS1820 and the microcontroller via RA11 or RE0 microcontroller pins. The
selection of either of those two lines is done using J9 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 1-wire), LEDs and additional pull-up or pull-down resistors
from the interface lines in order not to interfere with signal/data integrity.
Figure 15-1:
DS1820 not
connected
Figure 15-2:
DS1820
placed in
socket
Figure 15-3:
DS1820
connected
to RA11 pin
Figure 15-4:
DS1820
connected
to RE0 pin
Figure 15-5:
DS1820
connected
to RA11 pin
Enabling DS1820 Sensor
1
2
3
4
other modules
