4 ms·
The video clock (I assume you mean pixel clock) isn't relevant. The synchronization of video and audio happens on a per-frame basis. And since the frames are cl
by Scali 3y ago
The video clock (I assume you mean pixel clock) isn't relevant. The synchronization of video and audio happens on a per-frame basis.
And since the frames are clocked out on the audio-clock, there cannot be any drift.
- Scali 3y agoHaving said that, the CGA card does not actually have its own clock. It takes the NTSC base frequency of 14.31818 MHz from the OSC-pin of the ISA bus. On early PCs, such as the IBM 5150/5160, the CPU frequency is also derived from this same base clock (which is why you get the oddly specific speed of 4.77 MHz).