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EasyPIC6 Development System
MikroElektronika
page
12.0. LEDs
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limiting resistor the value of which is calculated using formula R=U/I where R is referred to resistance expressed in ohms, U is referred to
voltage on the LED and I stands for LED diode current. A common LED diode voltage is approximately 2.5V, while the current varies from
1mA to 20mA depending on the type of LED diode. The EasyPIC6 development system uses LEDs with current I=1mA.
The EasyPIC6 has 36 LEDs which visually indicate the logic state of each microcontroller I/O pin. An active LED diode indicates that
a logic one (1) is present on the pin. In order to enable LEDs, it is necessary to select appropriate port PORTA/E, PORTB, PORTC or
PORTD using the DIP switch SW9.
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Figure 12-2
: LED diode and PORTB connection schematic
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Figure 12-1
: LEDs
Notch indicating the
SMD LED cathode
SMD LED
R
I
R=U/I
472
A
K
RB3
RB4
RB5
RB6
RB7
Microcontroller
SMD resistor limiting current
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