Write to TFT whit 2 arduinos

I have a project where i have to monitor two devices, and constantly write to one TFT screen (via SPI), information about each individual process(half of screen for each process).
I was thinking about using one arduino and just switching fast beetwen each process and writing to one half of screen for couple of ms and few ms to other half of screen.
But now our design section decided they want some animation and drawing of some bitmaps for each screen and if i want that to work smoothly i need to use 2 atmegas 328, 1 for each process.
The screen i use is 2.8 TFT whit ILI9341 driver.
So any idea how could i sync TFT spi connection whit 2 atmegas?

So any idea how could i sync TFT spi connection whit 2 atmegas?

I don't think you can (spell).

You could send the data from one Arduino to the other one, that has the TFT attached.

i could but in that case i still have to constantly monitor for data coming to main arduino from slave. I will try protothreads option.

I will try protothreads option.

I can't imagine how that will help. The Arduino driving the TFT will have to do the same amount of work.

I would try sending a common clock signal to an external interrupt pin on each Arduino to allow selecting which one is currently writing to the screen. Then you could just optimize the clock period to give each Arduino enough time to write it's portion of the data to the screen.

thanks mstanley, if the the protothreads came out to be too much for one atmega, i will try your way and wire together 2.