how to increase the RAM address???

[admin]

I suggest you build a circuit out of two memory modules instead of increasing max address bits.

[Mwwhited]

Are there any known issues if the max allowed address was changed to 22 from 16?

[admin]

No known issues, but it will be too big blobs of memory to handle. It is hard to imagine your circuit will handle all that data in such big memory in reasonable time. If you need to simulate big address space you can have a smaller memory modules in a few ranges. Like in the smallest addresses and at the highest.