As for LCD, we have allowed GLCD back-light to be enabled in two
different ways:
1. It can be
turned on with full brightness
using
SW3.1
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
SW3.2
switch.
Graphical Liquid Crystal Displays
, or
GLCDs
are used to display
monochromatic graphical content, such as text, images, human-
machine interfaces and other content. EasyAVR
™
v7 provides
the connector and necessary interface for supporting GLCD with
resolution of 128x64 pixels, driven by the KS108 or compatible
display controller. Communication with the display module is
done through
CN16
display connector. Board is fitted with
uniquely designed plastic display distancer, which allows the
GLCD module to perfectly and firmly fit into place.
Display connector is routed to PB0, PB1, PA2,
PA3, PD6, PD7 (control lines) and PORTC (data
lines) of the microcontroller sockets. Since the
same ports are used by 2x16 character LCD display,
you cannot use both displays simultaneously. You
can control the display contrast using dedicated
potentiometer
P4
. Full brightness display back light
can be enabled with
SW3.1
switch, and PWM-driven
back light with
SW3.2
switch.
GLCD 128x64
VCC-5V
P4
10K
Q5
BC846
R34
20
R37
4K7
R36
1K
VCC-BRD
C
S1
C
S2
G
N
D
V
cc
V
o
R
S
R
/W
D
1
D
2
D
3
D
4
D
5
D
6
D
7
E
D
0
R
ST
V
ee
LE
D
+
LE
D
-
1
20
CN16
GLCD-TFT SOCKET2
PD7
PC7
PC6
PC5
PC4
PC3
PC2
PC1
PC0
PD6
PA3
PA2
PB1
PB0
DATA BUS
BCK PWM
BCK LIGHT
1
2
3
4
5
6
7
8
O
N
SW3
PD5
VCC-5V
GL
CD
BCK
PWM
displa
ys
Figure 11-1: GLCD 128x64
connection schematic
Standard and PWM-driven back-light
Connector pinout explained
In order to use PWM back-light both
SW3.1
and
SW3.2
switches must
be enabled at the same time.
IMPORTANT:
CS1
and
CS2
- Controller Chip Select lines
VCC
- +5V display power supply
GND
- Reference ground
Vo
- GLCD contrast level from potentiometer P4
RS
- Data (High), Instruction (Low) selection line
R/W
- Determines whether display is in Read or
Write mode.
E
- Display Enable line
D0–D7
- Data lines
RST
- Display reset line
Vee
- Reference voltage for GLCD contrast
potentiometer P3
LED+
- Connection with the back-light LED anode
LED-
- Connection with the back-light LED cathode
page 21
Easy
AVR
v7
