Hi Mahmood,

I haven't run across any OSD-type chips that give text and graphics. Chances are, if it existed it would require more horsepower to drive it than the 8051 has, if you have any kind of graphics resolution. If you happen to find one though, I'd love to hear about it!

You probably won't need to use it, but the mute output pin on the ST5730A doesn't work anything like the data sheet implies that it does. I've talked with another user of this part, and he wasn't able to figure out how to make use of it either. Not needed for normal cases where you are putting text on top of video, would be helpful to handle the case where external video goes away and you need to switch from mixed mode to full page mode. The most bothersome task was figuring out the best settings for the control and the mode registers, and finding the errors in the data sheet (e.g., M8 = 0 means VIDEO OUT2 is in low impedence state, not high impedence state).

It's a nice enough chip that we've stopped using regular displays for output, just use the nearest TV screen...

Have fun with it!

Dennis