I would agree that RAM is the overlooked weakness in 8051 enhancements' architecture.

The about two years ago I designed an 8051 circuit board with an external 128K bytes of RAM, the external static ram went obsolete and unavailable before we built the prototype. I didn't need that much, but I wanted a lot of elbow room. (By the way, I got by completely withing the internal RAM available).

But the more I used the 8051, the more I like this handicap because it forces me to use the existing SEGments more wisely.

However, it sure would be nice to have a big RAM internally for communications buffering. With FLASH systems capable to reprogram themsleves in system, this must be an oversight.

By the way, you might look to Philips XA (it basically a 16bit 8051) if you want to really do megabyte accessing. But prepare to pay for a completely new set of software compilers etc... the transition is toolwise unkind.

(I only use Philips microprocessors)
-Jay C. Box