GS4910B GENNUM [Gennum Corporation], GS4910B Datasheet - Page 66

• Manufacturer Part Number: GS4910B
• Description: HD/SD/Graphics Clock and Timing Generator with GENLOCK
• Manufacturer: GENNUM [Gennum Corporation]

Table 3-10: Audio Sampling Frequency to Video Frame Rate Synchronization
Audio Sample Rate (kHz)
* fps = frames per second.
44.1
32
48
4000/3
3675/2
24fps
2000
The external 10FID input pin may be used to resynchronize other audio clock
frequencies, according to
reference HSYNC of line 1 of the appropriate video frame. Please see
Section 3.4.2 on page 44
In the case where 10FID is not present as a reference signal, the GS4911B will
automatically generate an AFS pulse appropriate to the format selected, and use
it to create an audio frame sequence.
Host Interface Control of AFS and 10FID
Alternatively, the user may program the device via the host interface to re-time the
audio frame sequence and 10 field-ID. Using register 1Ah, a pulse may be
generated to reset the AFS and/or 10FID dividers at the start of an output video
frame (see
If using the host interface to reset the AFS pulse, the device may be configured to
ignore the input 10FID reference pin. To disable the signal on the external 10FID
pin from resetting the AFS output pulse, set bit 0 of the Audio_Control register
HIGH.
If using the host interface to reset the 10FID pulse, the external 10FID pin must be
grounded.
36655 - 2
25fps
1280
1764
1920
Section 3.12.3 on page
April 2006
147147/100
16016/15
Audio Samples per Video Frame
29.97fps
8008/5
for more details on the 10FID input pin.
Table
3-10, by applying an active signal during the
3200/3
30fps
1470
1600
79).
GS4911B/GS4910B Data Sheet
50fps
640
882
960
147147/200
59.94fps
8008/15
4004/5
66 of 113
1600/3
60fps
735
800