MIKROE-1385 mikroElektronika, MIKROE-1385 Datasheet - Page 23

• Manufacturer Part Number: MIKROE-1385
• Description: Development Boards & Kits - AVR EASY AVR V7 DEVELOPMENT SYSTEM
• Manufacturer: mikroElektronika

Specifications of MIKROE-1385

• Rohs: yes
• Product: Development Boards
• Tool Is For Evaluation Of: ATMEGA32 Devices
• Core: AVR
• Interface Type: mikroBUS socket, RS-232, USB
• Operating Supply Voltage: 3.3 V, 5 V
• Data Bus Width: 8 bit
• Dimensions: 266 mm x 220 mm
• For Use With: MIKROE-240, MIKROE-55

4 digit
7-seg display
One seven segment digit consist of 7+1
LEDs which are arranged in a specific
formation which can be used to represent
digits from 0 to 9 and even some letters.
One additional LED is used for marking
the decimal dot, in case you want to
write a decimal point in the desired
segment. EasyAVR
these digits put together to form 4-digit
7-segment display. Driving such a display
is done using multiplexing techniques.
Data lines are shared between segments,
and therefore the same segment LEDs in
each digit are connected in parallel. Each
digit has it’s unique digit select line,
EasyAVR
™
v7
v7 contains four of
which is used to enable the digit
to which the data is currently being
sent. By multiplexing data through all
four segments fast enough, you create
an illusion that all four segments are in
operation simultaneously.
This is possible because human eye has
a slower reaction time than the mention
changes. This way you can represent
numbers in decimal or hexadecimal form.
Eight data lines that are common for all
the digits are connected to PORTC, and
digit select lines are connected to PA0–
PA3 lines on the microcontroller sockets.
Figure 13-2: 4-digit 7-segment display schematic
DIS1
DIS0
R27
10K
R30
10K
COM1
COM0
Q3
BC846
Q4
BC846
Enabling the display
To enable digit select lines for the 4-digit
7-segment display you have to turn
on SW8.1, SW8.2, SW8.3 and SW8.4
switches. Digit select lines are connected
to PA0 – PA3 pins on the microcontroller
sockets, while data lines are connected to
PC0 – PC7 pins. Make sure to disconnect
other peripherals from the interface lines
in order not to interfere with signal/data
integrity.
DIS3
DIS2
R14
10K
R19
10K
COM3
COM2
Q1
BC846
Q2
BC846
DIS0
DIS1
DIS2
DIS3
SW8
PA0
PA1
PA2
PA3
Figure 13-1: Turn on switches
1 through 4 on SW8 to enable
4-digit 7-seg display
PC0
PC1
PC2
PC3
PC4
PC5
PC6
PC7
R1
R2
R3
R4
R5
R6
R7
R11
DATA BUS
470
470
470
470
470
470
470
470
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