Z90255 ROM

If Row, Second color and Character Z90255 ROM set are defined, an analog bar line can be displayed for volume control, signal levels, and tuning.

The OSD Z90255 ROM can display four character sizes:
• 1X (14 x 18 pixels)
• 2X (28 x 36 pixels)
• Double width (28 x 18 pixels)
• Double height (14 x36 pixels)

Inter-row spacing can be programmed within 0 to 15 Horizontal scan lines. Using multiple characters with zero inter-row spacing allows the creation of large psuedo icons.

A 14-bit Pulse Width Modulator (PWM) Z90255 ROM port provides necessary voltage resolution for a voltage synthesizer tuning system. Ten 6-bit PWM ports are used to control audio (base, treble, balance and volume) and video (contrast, brightness, color, tint and sharpness) signal levels.

There are 27 I/O pins grouped into four ports. These I/O pins can be configured through software to provide timing, status signals, serial and parallel input and output.

For real-time events, such as counting, timing and data communication, two on-chip counter/timers are implemented. The Z90255 is packaged in a 42-pin SDIP and provides an ideal, reliable solution for high-volume consumer television applications.