page 25
connectivity
page 25
Headers Buttons
LEDs
Figure 6-4: IDC10 male headers enable easy
connection with mikroElektronika accessory boards
With enhanced connectivity as one of the key features
of mikromedia
™
workStation v7, we have provided
four connection headers for each PORT
. I/O PORT
group contains two male IDC10 header (like
CN3 and
CN4
Figure 6-3
) and one 1x10 row of connection
pads (like
CN1 Figure 6-3
). There is
one more IDC10
header
available on the left side of the board next to
breadboard. IDC10 can be used to connect accessory
boards with IDC10 female sockets.
The logic state of
all microcontroller
digital inputs may
be changed using
push
buttons
.
Tri-state
DIP
switch
SW2
is
available for selecting which logic state will be applied
to corresponding MCU pin when button is pressed, for
each I/O port separately. If you, for example, place
SW2.1
in
VCC
position, then pressing of any push button in
GROUP0 I/O group will apply logic one to the appropriate
microcontroller pin. The same goes for
GND
. If DIP switch
is in the middle position neither of two logic states will
be applied to the appropriate microcontroller pin. You
can disable pin protection 220ohm resistors by placing
jumpers
J5
and
J6
, which will connect your push buttons
directly to VCC or GND. Be aware that doing so you may
accidentally damage MCU in case of wrong usage.
Figure 6-5: Button press level DIP
switch (tri-state)
In the far upper right section of the
board, there is a
RESET button
,
which
can be used to manually
reset the microcontroller. There
is an additional button at the
top of the mikromedia
™
board.
Reset Button
LED (Light-Emitting
Diode)
is a highly
efficient electronic
light source. When
connecting
LEDs,
it is necessary to
place
a
current
limiting resistor in
series so that LEDs
are provided with
the current value
specified by the manufacturer. The current varies from
0.2mA to 20mA, depending on the type of the LED
and the manufacturer. The mikromedia
™
workStation
v7 board uses low-current LEDs with typical current
consumption of 0.2mA or
0.3mA. Board contains 40
LEDs which can be used
for visual indication of the
logic state on PORT pins. An
active LED indicates that a
logic high (1) is present on
the pin. In order to enable
GROUP LEDs, it is necessary
to enable the corresponding
DIP switch on
SW3
(
Figure
6-6
).
Figure 6-6: SW3.1
through SW3.5
switches are used to
enable GROUP LEDs
G0.0
1
2
3
4
5
6
7
8
9
10
11
12
13
5V
GND
AN
AL
O
G
IN
T
SMD LED
SMD resistor
limiting current
through the LED
