NT68520XF Datasheet, PDF (27/97 Pages) List of Unclassifed Manufacturers – XGA,SXGA Flat Panel Monitor Controller

NT68520X,E
content registers (DCNT_HB, LCNT_HB) first, the H/V frequency will change after you
set the low byte contents registers (DCNT_LB, LCNT_LB).
DCNT_HB
DCNT_LB
Pre-Load
(EN_FREE = 0 1)
Auto Load
12MHz
EN_FRUN=1
1/DCNT
1/LCNT
Pre-Load
Auto Load
LCNT_LB
H_FREE
1us
EN_HRUN=1
V_FREE
8 lines
EN_VRUN=1
LCNT_HB
Free-Run Generator
Note：The Pulse width of the H_FREE is 1us, and that means it is equal to 12 dots under
12MHz OSC.
Fast Mute
1. The block generates a fast mute interrupt, INT_FM, to indicate an actable state of
horizontal frequency. The operations of this block are A H-Period Counter counts the
12MHz pulse number within a period of the horizontal sync, and gets the current
value A
2. The previous stable H-Period Latch held the previous counter value B.
3. Subtract or obtains a difference C from A and B, then B will be replaced with A for
updating the next previous value.
4. C is compared with the difference boundary value DIFF_VAL written by user.
2003/4/15
27
Ver.1.0