Bank switching with 8 bit bank address is a way to acheive 24-bit addressing with an 8052!!

There is no doubt that if you have a real 4M byte data base to search through that any 8052 implementation will be somewhat more complicated (and slower) than a processor with direct 24-bit address bus.

This is one of the reasons why there are so many different kinds of processors on the market. There are many different application requirements and each takes a different cost/performance ratio to achieve an effective end product!

Michael Karas