M I K R O E L E K T R O N I K A S O F T W A R E A N D H A R D W A R E S O L U T I O N S F O R T H E E M B E D D E D W O R L D
1
17
7
page
EasyAVR
USB
4
EasyAVR4 User
’
s Manual
MikroElektronika
Development
tools
PP
UU
SS
HH
BB
UU
TT
TT
OO
NN
SS
WW
IITT
CC
HH
EE
SS
VCC
RA0
RA1
RA2
RA3
RA4
RA5
RA6
RA7
RB0
RB1
RB2
RB3
RB4
RB5
RB6
RB7
RC0
RC1
RC2
RC3
RC4
RC5
RC6
RC7
RD0
RD1
RD2
RD3
RD4
RD5
RD6
RD7
PORTA
PORTB
PORTC
PORTD
0V while button
is pressed
+5V while button
is pressed
J6
A
TMEGAxxxx
PB1
PB2
PB3
PB4
PD1
PD2
PB5
PB6
PB7
PD4
PD5
PD6
PC1
PC0
PD7
PC2
PC3
PC4
PC5
PC6
PC7
PA7
PA6
PA5
PA4
PA3
PA2
PA0
PA1
PD3
PB0
PD0
RST
VCC
GND
XT2
XT1
AREF
AGND
AVCC
VCC
OSCILLATOR
10K
Reset
100n
VCC
Figure 19.
Buttons schematic
Buttons connections to PORTA, PORTB, PORTC and PORTD are shown in Fig. 19. Jumper
J6 determines whether a button press will bring logical zero or logical one to the appropri-
ate pin.
When button is not pressed, pin state is determined by the pull-up or pull-down port
jumpers.
In the example shown in Fig. 19, J6 is connected to +5V, therefore pressing the buttons will
bring logical one to the appropriate pins.
