Chameleon-AVR Nurve Networks, Chameleon-AVR Datasheet - Page 54

• Manufacturer Part Number: Chameleon-AVR
• Description: MCU, MPU & DSP Development Tools AVR8 & PROPELLER DEV SYSTEM (SBC)
• Manufacturer: Nurve Networks

Specifications of Chameleon-AVR

• Processor To Be Evaluated: AVR 328P
• Data Bus Width: 8 bit
• Interface Type: USB, VGA, PS/2, I2C, ISP, SPI
• Operating Supply Voltage: 3.3 V, 5 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Prop Port Bit/Pin
P27
P26
In the section below general keyboard and mouse operation is described, so you can write your own drivers if you wish.
The driver we used for the Propeller driver supports both keyboard and mouse, but its not integrated thus a core is
needed for each driver object – a bit wasteful.
12.1 Keyboard Operation
The keyboard protocol is straightforward and works as follows; for every key pressed there is a "scan code" referred to
as the "make code" that is sent, additionally when every key released there is another scan code referred to as the
"break code" that in most cases is composed of $E0 followed by the original make code scan value. However, many
keys may have multiple make codes and break codes. Table 12.2 lists the scan codes for keyboards running in default
mode (startup).
KEY
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
0
MAKE
1C
32
21
23
24
2B
34
33
43
3B
42
4B
3A
31
44
4D
15
2D
1B
2C
3C
2A
1D
22
35
1A
45
NOTE
BREAK
F0,1C
F0,32
F0,21
F0,23
F0,24
F0,2B
F0,34
F0,33
F0,43
F0,3B
F0,42
F0,4B
F0,3A
F0,31
F0,44
F0,4D
F0,15
F0,2D
F0,1B
F0,2C
F0,3C
F0,2A
F0,1D
F0,22
F0,35
F0,1A
F0,45
As noted, the PS/2 interface works the same for keyboards and mice, the protocols are
different, but the low level serial and hardware interfaces are the same. Thus, if you plug
a mouse into the port, it would work the same, the clock and data lines would be in the
same place. Thus, all you would have to do is write the driver.
Chameleon Signal
PS2_CLOCK
PS2_DATA
Table 12.1 – PS/2 connector interface to Chameleon AVR.
L SHFT
L CTRL
R SHFT
R CTRL
SPACE
L GUI
L ALT
R GUI
R ALT
ENTER
BKSP
CAPS
APPS
KEY
TAB
ESC
F1
F2
F3
F4
F5
F6
F7
9
`
-
=
\
Table 12.2 – Default scan codes.
Description
Keyboard clock signal, open collector.
Keyboard data signal, open collector.
E0,1F
E0,14
E0,27
E0,11
E0,2F
MAKE
46
0E
4E
55
5D
66
29
0D
58
12
14
11
59
5A
76
05
06
04
0C
03
0B
83
.
E0,F0,1F
E0,F0,14
E0,F0,27
E0,F0,11
E0,F0,2F
© 2009 NURVE NETWORKS LLC “Exploring the Chameleon AVR 8-Bit”
BREAK
F0,46
F0,0E
F0,4E
FO,55
F0,5D
F0,66
F0,29
F0,0D
F0,58
FO,12
FO,14
F0,11
F0,59
F0,5A
F0,76
F0,05
F0,06
F0,04
F0,0C
F0,03
F0,0B
F0,83
U ARROW
L ARROW
D ARROW
R ARROW
INSERT
DELETE
PG UP
PG DN
KP EN
HOME
KP /
KP *
KP -
KP +
KP .
KP 0
KP 1
KP 2
KP 3
KP 4
KP 5
KP 6
KP 7
KP 8
KEY
END
NUM
[
MAKE
E0,70
E0,6C
E0,7D
E0,71
E0,69
E0,7A
E0,75
E0,6B
E0,72
E0,74
E0,4A
E0,5A
54
77
7C
7B
79
71
70
69
72
7A
6B
73
74
6C
75
E0,F0,70
E0,F0,6C
E0,F0,7D
E0,F0,71
E0,F0,69
E0,F0,7A
E0,F0,75
E0,F0,6B
E0,F0,72
E0,F0,74
E0,F0,4A
E0,F0,5A
BREAK
FO,54
F0,77
F0,7C
F0,7B
F0,79
F0,71
F0,70
F0,69
F0,72
F0,7A
F0,6B
F0,73
F0,74
F0,6C
F0,75
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