M37281MAH
–
XXXSP,M37281MFH
–
XXXSP,M37281MKH
–
XXXSP, M37281EKSP
Rev.1.01 2003.07.16 page 116 of 170
8.11.18 OSD Output Pin Control
The OSD output pins R(R1), G(G1), B(B1) and OUT1 can also func-
tion as ports P5
2
to P5
5
. Set the corresponding bit of the OSD port
control register (address 00CB
16
) to
“
0
”
to specify these pins as OSD
output pins, or set it to
“
1
”
to specify it as a general-purpose port P5
pin.
Pins R0, G0 and B0 can also function as ports P1
7
, P1
5
and P1
6
,
respectively. Set bit 1 of the OSD port control register to
“
0
”
to specify
these pins as a general-purpose output port P1 pin, or set it to
“
1
”
to
specify it as OSD output pins. When
“
0,
”
4-adjustment-level analog
output is output from pins R, G and B. When
“
1,
”
the value which is
converted from the analog to the 2-bit digital is output as follows: the
high-order bit is output pins R1, G1 and B1 and the low-order bit is
output from pins R0, G0 and B0.
The OUT2 can also function as Port P1
0
. Set bit 0 of the port P1
direction register (address 00C3
16
) to
“
1
”
(output mode). After that,
set bit 6 of the OSD port control register to
“
1
”
to specify the pin as
OSD output pin, or set it to
“
0
”
to specify as port P1
0
pin.
The input polarity of the H
SYNC
, V
SYNC
and output polarity of signals
R, G, B, OUT1 and OUT2 can be specified with the I/O polarity con-
trol register (address 0217
16
). Set a bit to
“
0
”
to specify positive
polarity; set it to
“
1
”
to specify negative polarity (refer to Figure 8.11.18).
The OSD port control register is shown in Figure 8.11.56.
Fig. 8.11.56 OSD Port Control Register
b7 b6 b5 b4 b3 b2 b1 b0
0
OSD port control register (PF) [Address 00CB
16
]
b
Name
Functions
After reset
R W
OSD Port Control Register
0
0
R W
Fix this bit to
“
0
”
0
2
0 : R signal output
1 : Port P5
2
output
0
R W
3
Port P5
3
output signal
selection bit (G)
0 : G signal output
1 : Port P5
3
output
0
R W
4
Port P5
4
output signal
selection bit (B)
0 : B signal output
1 : Port P5
4
output
0
R W
5
Port P5
5
output signal
selection bit (OUT1)
0 : OUT1 signal output
1 : Port P5
5
output
0
R W
6
Port P1
0
output signal
selection bit (OUT2)
0 : Port P1
0
signal output
1 : OUT2 output
0
R W
Port P5
2
output signal
selection bit (R)
7
0
R W
Fix this bit to
“
0
”
1
0 : 4-adjustment-level analog is
output from pins R, G, B.
1 : Value which is converted
from 4-adjustment-level
analog to 2-bit digital is
output as below:
High-order: from R1, G1, B1
Low-order: from R0, G0, B0
0
R W
R, G, B output method
selection bit (RGB2BIT)
Note:
When using ports P5
2
to P5
4
as general-purpose pins, set bit 2 of OSD
control register 2 (address 0215
16
) to
“
0.
”