This application note describes the two types of memory modes offered by the eZ80 CPU and provides a simple application to demonstrate how to properly configure the eZ80 CPU for a mixed memory mode of operation. As a result, you will be able to run blocks of legacy Z80 code from within the eZ80 CPU environment.
The eZ80 CPU offers two types of memory modes: Z80 Mode and Address Data Long (ADL) Mode. Z80 Mode offers backward compatibility with legacy Z80 applications, while ADL Mode offers 24-bit linear addressing and 24-bit CPU registers. These multiple memory modes of the eZ80 processor allow developers to easily migrate older Z80 or Z180 codes to the new ADL Mode codes.
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