CS89712
2.19.1 Free Running Mode
In the free running mode, the counter will wrap
around to 0xFFFF when it under flows and it will
continue to count down. Any value written to TC1
or TC2 will be decremented on the second edge of
the selected clock.
2.19.2 Prescale Mode
In the prescale mode, the value written to TC1 or
TC2 is automatically re-loaded when the counter
under flows. Any value written to TC1 or TC2 will
be decremented on the second edge of the selected
clock. This mode can be used to produce a pro-
grammable frequency to drive the buzzer (i.e., with
TC1) or generate a periodic interrupt. The formula
is F=(500 kHz) / (n+1).
2.20 Real-Time Clock
The CS89712 contains a 32-bit Real-Time Clock
(RTC). This can be written to and read from in the
Pixel 1 Pixel 2 Pixel 3 Pixel 4
Gray scale
Gray scale
Bit 0 Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6 Bit 7
4 Bits per pixel
Pixel 1 Pixel 2 Pixel 3 Pixel 4
Gray scale Gray scale Gray scale Gray scale
Bit 0 Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6 Bit 7
2 Bits per pixel
Pixel 1 Pixel 2 Pixel 3 Pixel 4
Gray scale Gray scale Gray scale Gray scale
Bit 0 Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6 Bit 7
1 Bit per pixel
Figure 11. Video Buffer Mapping
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DS502PP2