mikroElektronika EasyPIC v7, Руководство пользователя

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Easy PIC
for dsPIC30
®
v7
page 24
Liquid Crystal Displays or LCDs are cheap and
popular way of representing information to the
end user of some electronic device. Character
LCDs can be used to represent standard and
custom characters in the predefined number
of fields. EasyPIC
™
v7 for dsPIC30
®
provides the
connector and the necessary interface for supporting
2x16 character LCDs in 4-bit mode. This type of
display has two rows consisted of 16 character fields.
Each field is a 7x5 pixel matrix. Communication with the
display module is done through CN7 display connector. Board
is fitted with uniquely designed plastic display distancer, which
allows the LCD module to perfectly and firmly fit into place.
GND
and
VCC
- Display power supply lines
Vo
- LCD contrast level from potentiometer P4
RS
- Register Select Signal line
E
- Display Enable line
R/W
- Determines whether display is in Read or Write mode. It’s
always connected to GND, leaving the display in Write mode all
the time.
D0–D3
- Display is supported in 4-bit data mode, so lower half of
the data byte interface is connected to GND.
D4–D7 - Upper half of the data byte
LED+
- Connection with the back light LED anode
LED-
- Connection with the back light LED cathode
We have allowed LCD back light to be enabled in two different ways:
1. It can be turned on with full brightness using SW10.8 switch.
2. Brightness level can be determined with PWM signal from the
microcontroller, allowing you to write custom back light controlling
software. This back light mode is enabled with SW10.7 switch.
LCD 2x16 characters
1 2 3 4 5 6 7 8 O
N
SW10
BCK LIGHT
VCC-5V
RB10
Vs
s
Vd
d
Ve
e
R
S
R
/W
E
D
0
D
1
D
2
D
3
D
4
D
5
D
6
D
7
A K
CN7
LCD SOCKET
VCC-5V
P1
10K
VCC-5V
Q5
BC846
R18
56
R22
4K7
R21
1K
VCC-BRD
BCK PWM
BC
K
LI
G
H
T
LC
D
B
CK
P
W
M
R
B0
R
B1
R
B2
R
B3
R
D
0
R
D
1
VE
E
DATA BUS
Figure 11-1: On-board LCD 2x16 display connector
Figure 11-2: 2x16 LCD
connection schematics
Standard and PWM-driven back light
Connector pinout explained
Make sure to turn off the power supply before placing LCD onto
the board. Otherwise your display can be permanently damaged.
In order to use PWM back light both SW10.7 and SW10.8 switches must
be enabled at the same time.
IMPORTANT:
IMPORTANT:
displa
ys