... which is why you have to read the datasheet for each variant you're considering.

Many of the classic 805x types provide that multiplexed external address and data bus controlled by nRD, nWR, nPSEN, and ALE. Some of the newer ones do not, however.

The SiLabs 'F12's have more ways of interfacing external memory than that, including a non-multiplexed bus. As I've pointed out, they also support I2C and SPI with hardware. Further, they allow you to modify the external bus timing if you find it necessary.

I urge you to read the datasheet for the SiLabs 'f12x-series just to give you a detailed look at all the features. They're very capable, though they require firm understanding. That, in fact, is true of nearly any MCU.

I don't recommend using wire-wrap unless you require quick turn-around. I can wrap a circuit on the order of the one you've suggested you're using, in about an hour, including very excellent power supply bypass, which is very important in any prototype. When I'm finished, I can salvage all the sockets and even some of the bypass cap's, though the small SMT passives are generally sacrificed. Wire-wrapped circuits are generally very robust and tolerate much "fiddling" as part of the process of startup. I mention this only because some people believe it a good idea to use a "ProtoBoard", with those inserted wires to make connections. They are very fragile and often are intermittent in their behavior.

RE