Z90251 Datasheet, PDF (34/97 Pages) Zilog, Inc. – eZVision 200 Television Controllers with OSD

Z90255 ROM and Z90251 OTP
32 KB Television Controller with OSD
26
The Second Color feature can be used to implement an analog bar for volume
control, tuning, etc. The change step for color is half the character size. Refer to
Tables 8 and 9.
Second Color Control Register
The Second Color Position is the place where the foreground color changes to the
color defined in the Second Color Control Register.
Table 11 Second Color Control Register 07h:Bank A (SNDCLR_CNTRL)
Bit
7
6
5
4
3
2
1
0
R/W
R/W R/W R/W R/W R/W R/W R/W R/W
Reset
0
0
0
0
0
0
0
0
Note: R = Read W = Write X = Indeterminate
Bit/
Field
Second Color Enable
Second Color
Row Address
Bit
Position R/W Value Description
7
R/W
6, 5, 4 R/W
3, 2, 1, 0 R/W
0 Disables the second color feature
1 Enables the second color feature
R, G, B respectively. Defines the
second color after the second color
position defined in SNDCLR register.
Defines one of the 10 rows (from 0, the
first row, to 9, the 10th row).
Second Color Register
Table 12 Second Color Register 08h:Bank A (SNDCLR)
Bit
7
6
5
4
3
2
1
0
R/W
Reset
R/W R/W R/W R/W R/W R/W R/W R/W
x
0
0
0
0
0
0
0
Note: R = Read W = Write X = Indeterminate
PS001301-0800