18
UNI-DS3 Development System
MikroElektronika
page
14.0. LEDs
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resistor. A common LED diode voltage is approximately 2.5V, while the current varies from 1 to 20mA depending on the type of LED.
The
UNI-DS3
uses LEDs with current I=1mA.
There are 72 LEDs on the
UNI-DS3
development system which visually indicate the state of each microcontroller I/O pin. An active
LED indicates that a logic one (1) is present on the pin. In order to enable the pin state to be shown, it is necessary to select
appropriate port (PORTA, PORTB, PORTC, PORTD, PORTE, PORTF, PORTG, PORTH or PORTJ) using the DIP switch SW1 and
switch 1 on the DIP switch SW2.
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: LEDs and ports PORTB and PORTC connection schematic
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: LEDs
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Resistor network used to
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