NEC XP29 Plus - Manual (Page 35)

Composite Sync. & Video (Sync. on Green)
Recommended Sync Signal Timing
Horizontal Duty should be 3 to 30%.
Horizontal sync width should exceed 0.9 µ sec.
Horizontal back porch should exceed 2.0 µ sec at sync on green and 1.2 µ sec at others except when at 15KHz.
Horizontal blanking should exceed: 15.75; 10 µ sec, 31KHz< fH<66KHz: 3.6 µ sec, 66KHz<fH: 2.7 µ sec.
Vertical Duty should be 0.2 to 10%.
Vertical sync width should exceed 40 µ sec or 2 horizontal lines.
Vertical sync width plus back porch should exceed 0.4 msec.
Interlaced signals are not recommended.
Interlaced signals with composite sync may not be displayed.
A
B C D E
VIDEO
O
P Q R S P
VIDEO
Sync. Polarity: Negative
HORIZONTAL
VERTICAL
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