Digital Clock Using PCA21125
This project introduces the use of PCA21125 as
one of the components of this digital clock. It is a real time clock
made in CMOS technology and calendar optimized for low-power consumption
with an operating temperature up to 125 degree Celsius. Data is
transferred via a Serial Peripheral Interface (SPI-bus) with a maximum
data rate of 6 Mbit/s. The device displays the current time and date
with the use of an LCD.
ATMEGA8 microcontroller was
chosen for its high prevalence and low price. This microcontroller can
be used as a DIP- housing 28 and a housing SMD execution TQFP- 32.
Resistor R3 is needed to prevent random noise at terminal PC6. The LCD
display is connected to the microcontroller for four-bit system. The
variable resistor R2 is required to adjust the contrast of displayed
symbols. Rotating this resistor obtains the most precise indications on
the screen. The LCD backlight is organized through the conclusion of "A"
and "K" on the display board. The backlight is turned through the
current limiting resistor - R1. The higher the value, the dimmer the
display will light. The LED may be replaced by any audio circuitry,
which responds to a signal from the microcontroller. Managing the clock
setting is carried out by means of the buttons S1 - S4.
Digital
clocks had remarkably benefitted us for its accurate and readable time
display. This can be observed in a wide range of applications such as in
appliances, computers, automotive technology and industrial equipment
where time is considerably observed.
one of the components of this digital clock. It is a real time clock
made in CMOS technology and calendar optimized for low-power consumption
with an operating temperature up to 125 degree Celsius. Data is
transferred via a Serial Peripheral Interface (SPI-bus) with a maximum
data rate of 6 Mbit/s. The device displays the current time and date
with the use of an LCD.
ATMEGA8 microcontroller was
chosen for its high prevalence and low price. This microcontroller can
be used as a DIP- housing 28 and a housing SMD execution TQFP- 32.
Resistor R3 is needed to prevent random noise at terminal PC6. The LCD
display is connected to the microcontroller for four-bit system. The
variable resistor R2 is required to adjust the contrast of displayed
symbols. Rotating this resistor obtains the most precise indications on
the screen. The LCD backlight is organized through the conclusion of "A"
and "K" on the display board. The backlight is turned through the
current limiting resistor - R1. The higher the value, the dimmer the
display will light. The LED may be replaced by any audio circuitry,
which responds to a signal from the microcontroller. Managing the clock
setting is carried out by means of the buttons S1 - S4.
Digital
clocks had remarkably benefitted us for its accurate and readable time
display. This can be observed in a wide range of applications such as in
appliances, computers, automotive technology and industrial equipment
where time is considerably observed.
