M37221 Mitsubishi, M37221 Datasheet - Page 47

• Manufacturer Part Number: M37221
• Description: SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER for VOLTAGE SYNTHESIZER with ON-SCREEN DISPLAY CONTROLLER
• Manufacturer: Mitsubishi

(8) CRT Output Pin Control
The CRT output pins R, G, B, and OUT1 can also function as ports
P5
rection register (address 00CB
output pins, or set it to “1” to specify it as an general-purpose port P5
pins. The OUT2 pin can also function as port P1
CRT control register (address 00EA
set it to “1” to specify it as OUT2 pin.
The input polarity of signals H
signals R, G, B, and OUT1 can be specified with the bits of the CRT
port control register (address 00EC
positive polarity; set it to “1” to specify negative polarity. The struc-
ture of the CRT port control register is shown in Figure 50.
(9) Raster Coloring Function
An entire screen (raster) can be colored by setting the bits 5 to 7 of
the CRT port control register. Since each of the R, G, and B pins can
be switched to raster coloring output, 7 raster colors can be obtained.
If the R, G, and B pins have been set to MUTE signal output, a raster
coloring signal is output in the part except a no-raster colored char-
acter (in Figure 51, a character “O”) during 1 horizontal scanning
period. This ensures that character colors do not mix with the raster
color. In this case, MUTE signal is output from the OUT1 pin.
An example in which a magenta character “I” and a red character “O”
are displayed with blue raster coloring is shown in Figure 51.
Fig. 51. Example of raster coloring
R
OUT1
H
B
2
, P5
SYNC
3
A
, P5
4
and P5
5
. Set the corresponding bit of the port P5 di-
SYNC
16
) to “0” to specify these pins as CRT
16
and V
16
) to “0” to specify it as port P1
) . Set a bit to “0” to specify
SYNC
and output polarity of
A'
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER for VOLTAGE SYNTHESIZER
0
. Set bit 7 of the
Signals
across
A – A'
“RED”
“BLUE”
0
,
M37221EF-XXXSP,M37221EFSP
Fig. 50. Structure of CRT port control register
7
with ON-SCREEN DISPLAY CONTROLLER
0
CRT port control register
(CRTP : address 00EC
R, G, B output polarity switch
bit
OUT1 output polarity switch
bit
R signal output switch bit
B signal output switch bit
H
bit
V
bit
OUT2 output polarity switch
bit
G signal output switch bit
SYNC
SYNC
0 : Positive polarity
1 : Negative polarity
0 : Positive polarity
1 : Negative polarity
0 : R signal output
1 : MUTE signal output
0 : B signal output
1 : MUTE signal output
0 : Positive polarity
1 : Negative polarity
0 : Positive polarity
1 : Negative polarity
0 : Positive polarity
1 : Negative polarity
0 : G signal output
1 : MUTE signal output
input polarity switch
input polarity switch
16
)
47