Kevin Liao wrote: > > Sorry, I don't whether it's a stupid question. But what are genlock, 4066, PIC and LM1881? Is LM1881 just like TDA8540? Thanks a > lot! Genlock is jargon for multiple video signals being locked onto an external clock, so they are all in sync. This means that switching from one signal to another at any time will not cause any glitch in the image. A 4066 is an inexpensive CMOS integrated circuit that contains an array of analog switches. It can be used to route video. A PIC is an inexpensive microcontroller made by Microchip. The LM1881 (http://www.national.com/ds/LM/LM1881.pdf) is a video sync separator IC that outputs the vertical and horizontal pulses from a composite video signal at the input. The TDA8540 is a 4X4 crosspoint switch IC, that can route four signals to four outputs. (http://www.semiconductors.philips.com/acrobat/datasheets/TDA8540_3.pdf) Martin
