14
EasyPIC6 Development System
MikroElektronika
page
9.0. USB Communication
The
USB
connector enables PIC microcontrollers with a built-in USB communication module to be connected to peripheral components. In
order to enable USB communication, it is necessary to change the position of jumpers J12 from left-hand to right-hand, thus connecting the USB
DATA lines (D+ i D-) to RC4 and RC5 microcontroller pins and the RC3/VUSB pin to capacitors C16 and C17. If USB communication is not used,
jumpers J12 should be left in the left-hand position. The status of USB communication (OFF/ON) is indicated by LED. Figures 9-3 and 9-4 show
schematics of the most commonly used microcontrollers with integrated USB module.
Figure 9-1
: USB communication
disabled (default position)
Figure 9-2
: USB communication
enabled
USB connector
VCC-MCU
VCC-MCU
X1
8MHz
C6
22pF
C7
22pF
PIC18F4550
OSC2
RC0
RC1
RC2
RC3/VUSB
RD0
RD1
OSC1
GND
GND
RD7
RD6
RD5
RD4
RC7
RC6
RC5
RC4
RD3
RD2
VCC
MCLR
RA0
RA1
RA2
RA3
RA4
RA5
RE0
RE1
RE2
VCC
RB0
RB1
RB2
RB3
RB4
RB5
RB6
RB7
DIP40
RC3
RC4
RC5
J12
CN4
USB B
D+
GND
VCC-BUS
D-
R42
4K7
LD44
USB ON
C16
100nF
C17
100nF
Bottom view
VCC
GND
D+
D-
Figure 9-3
: PIC18F4550 USB communication schematic
RC3
RC4
RC5
J12
CN4
USB B
D+
GND
VCC-BUS
D-
R42
4K7
LD44
USB ON
C16
100nF
C17
100nF
Bottom view
VCC
GND
D+
D-
VCC-MCU
X1
8MHz
C6
22pF
C7
22pF
DIP28
RB6
RA0
RB5
RA1
RB4
RA2
RB3
RA3
RB2
RA4
RB1
RA5
RB0
GND
VCC
GND
RC7
RC6
RC5
RC4
OSC1
OSC2
RC0
RC1
RC2
RC3
RB7
MCLR
PIC18F2550
Figure 9-4
: PIC18F2550 USB communication schematic
J u m p e r
J12 in the
left-hand
position
J u m p e r
J12 in the
left-hand
position
