7220 Datasheet, PDF (187/303 Pages) Renesas Technology Corp – 8-BIT SINGLE-CHIP MICROCOMPUTER

APPLICATION
5.2 Notes on programming for OSD (M37220M3-XXXSP/FP)
Color Register n
b7 b6 b5 b4 b3 b2 b1 b0
Color register n (COn) (n = 0 to 3) [Addresses 00E6 16 to 00E916]
B
Name
Functions
0 Nothing is assigned. This bit is a write disable bit.
When this bit is read out, the value is “0.”
1 B signal output
selection bit (COn1)
2 G signal output
selection bit (COn2)
0 : No character is output
1 : Character is output
0 : No character is output
1 : Character is output
3 R signal output
selection bit (COn3)
0 : No character is output
1 : Character is output
4 _{Nothing is assigned. This bit is a write disable bit.}
When this bit is read out, the value is “0.”
5 OUT signal output
control bit (COn5)
0 : Character is output
1 : Blank is output
6, 7 Nothing is assigned. These bits are write disable bits.
When these bits are read out, the values are “0.”
Fig. 5.2.2 Color register n (M37220M3-XXXSP/FP)
After reset R W
0 R—
0 RW
0 RW
0 RW
0 R—
0 RW
0 R—
5.2.2 Setting border selection register
The M37220M3-XXXSP/FP can output neither character background (OUT) nor border at the same time.
When setting the border selection bits (bit 0 or 2) to “1,” the border output takes over OUT (setting of
bit 5 of the color registers). Therefore, select either the character background output or the border output.
Border Selection Register
b7 b6 b5 b4 b3 b2 b1 b0
Border selection register (MD) [Address 00E5 16]
B
Name
Functions
0 Block 1 OUT output
0 : Same output as character output
border selection bit (MD10) 1 : Border output
1 Nothing is assigned. This bit is a write disable bit.
When this bit is read out, the value is “0.”
2 Block 2 OUT output
0 : Same output as character output
border selection bit (MD20) 1 : Border output
3 Nothing is assigned. These bits are write disable bits.
to
7
When these bits are read out, the values are “0.”
After reset R W
Indeterminate R W
0
R—
Indeterminate R W
0
R—
Fig. 5.2.3 Border selection register (M37220M3-XXXSP/FP)
5.2.3 Number of display characters
The M37221ERSS can display up to 24 characters in each block. However, the M37220M3-XXXSP/FP can
display only up to 20 characters in each block. Note this when programming using the M37220M3-XXXSP/
FP.
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7220 Group User’s Manual