Z90251 Datasheet, PDF (46/97 Pages) Zilog, Inc. – eZVision 200 Television Controllers with OSD

Z90255 ROM and Z90251 OTP
32 KB Television Controller with OSD
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The Hex Add column is a hexadecimal number that serves as an address for the
group of pixels from the starting point of the scan line. Addressing begins at
0000h and ends at 0023h for the first character. There is an address gap
between characters. The starting address for the second character is 0040h.
Each bit in the map sets the foreground/background designation of the
corresponding pixel:
0 background pixel
1 foreground pixel
The patterns formed by the bits comprise the characters that are displayed when
the scan line is output to the screen.
Each of these character pixel maps is one character; 512 characters can be
mapped.
Several characters can be combined to form a large icon. Figures 13 is an
example of a large icon. Each block marked by the darker grid lines is 14 x 18
pixels, one character.
Row 4
No Spacing
Row 5
No spacing
Row 6
6HL
Spacing
Row 7
Fringing Effect
Figure 13 Example of a Multiple Character Icon
PS001301-0800