Can TVout handle 10 bytes data input during vertical sync ?

I am aware that TV out is a very old library, and interrupt driven, so uses nearly all of the timers resources.

There are also many versions of the library with different options, like polllserial, but it looks like that is for when you have the computer connected.

I have searched and apart from Nicks I2C answer a few years back, I have struggled to see if I can add say 10 bytes of data from a second chip, perhaps during the vertical sync period ?

One version of a project I am thinking of now receives the 433 Mhz VirtualWire ( VW ) signal from all the existing transmitters that I have made over the last 10 years.

For the simplest option of this project , I want to receive and parse the data from the units, and display them on the AV input of a TV.

( later on I want to move on to Processing and IOT versions )

This first one would be a DC powered embedded unit with just an antenna , 5 v in, and an AV video out.

There are only a maximum of say 10 bytes of data I want to display on the TV.

I have TVout displaying the demo modes OK ( after swapping the pin 9 and pin 8 as the data out on some libraries is wrong ! )

I can change the data displayed, once I have the 8 variables , but I need it to " grab" the 8 bits of data from maybe a second 328chip .

Any ideas here ? I did search but nothing helping what I want to do.

People are using TVout for video games with joysticks so there must be a way to input new data, but I can't quite figure it out . ( the screen image seems to become unstable when I add too much data to display anyway so it must be rather touchy ? )_

I think that 433 MHz and other RF or network modules use much faster and powerful controllers than a 328. So the bottleneck is a small Arduino, not data transmission. But using a faster Arduino may require a deep rewrite of the TVout library, or has it already been done?