User`s guide

DQ
RA4
RE2
VCC-MCU
J11
R2
1K
VCC
DQ
GND
DATA BUS
DS1820 - Digital
Temperature Sensor
DS1820 is a digital temperature
sensor that uses 1-wir
interface for it’s operation. It is
capable of measuring temperatures
within the range of -55 to 128°C,
and provides ±0.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.
EasyPIC
v7 provides a separate socket
(TS1) for the DS1820. Communication
line with the microcontroller is connected
via jumper J11.
EasyPIC
v7 enables you to establish 1-wire® communication between DS1820
and the microcontroller via RA4 or RE2 microcontroller pins. The selection of either
of those two lines is done using J11 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 RE2 pin
Figure 15-4:
DS1820
connected
to RA4 pin
Figure 15-5:
DS1820
connected
to RE2 pin
Enabling DS1820 Sensor
1 2 3 4
page 28
modules