W78C354 Datasheet, PDF (32/44 Pages) Winbond – MONITOR MICROCONTROLLER

W78C354
FCLOCK
1/Fclock
Min. Vsync width (Wvmin)
VOUT delay from VIN (Tdelay)
16 MHz
62.5 nS
8031 ± 31 nS
8031 ± 31 nS
18.432 MHz
54 nS
6939 ± 27 nS
6939 ± 27 nS
20 MHz
50 nS
6425 ± 25 nS
6425 ± 25 nS
1. Withot composite sync
HIN
VIN
HOUT
VOUT
2. With composite sync
W_vmin
Tdelay
H IN(H+V)
V IN
HOUT
VOUT
Ò _{Figure 12. Vsync separator output (when DUMMYEN = 0, ENVS = 1)}
M-3. Horizontal & Vertical Frequency Counter
There are two 16-bit counters that automatically count the horizontal and vertical frequency. When a
VEVENT interrupt occurs, the W78C354 reads the count value (HCOUNT and VCOUNT) from the 8-bit
counter registers (HFCOUNTH, HFCOUNTL, VFCOUNTH, and VFCOUNTL) to calculate the H and V
frequency by the formulas listed below.
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