MB87P2020 Datasheet, PDF (177/356 Pages) Fujitsu Component Limited. – Colour LCD/CRT/TV Controller

xstart
timing coordinate space
xstop
ystart
Graphic Processing Unit
current position
14
X
0 F 14
Y
0
ystop
14
X
0 F 14
Y
0
don’t-care vector OFF
==
match position OFF
14
X
0 F 14
Y
0
14
X
0 F 14
Y
0
don’t-care vector ON
==
match position ON
14
X
0 F 14
Y
0
S
R
Figure 3-8: Matching positions with sync pulse generators.
SPG out
The output of a sync pulse generator is set or reset if the current position equals the respective programma-
ble position in all bits for which its don’t-care-vector (which is also programmable) contains zeros.The Off-
matching is dominant, i.e. when both, On and Off position are matched at the same time, the output of the
sync pulse generator is reset.
3.10.3 Sequence Matching
A more sophisticated yet more powerful approach to form first-stage signals is the application of a sequenc-
er RAM to match a whole sequence of positions. Fig. 3-9 shows the principle of operation.
There is one sync sequencer (SyncSeq) which is able to follow an arbitrary sequence of timing positions
and generate an appropriate output signal. The length of the sequence as well as the contents of the RAM,
consisting of position and the assigned output value are programmable.
GPU Control Information
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