OVERVIEW OF THE 80C186 FAMILY ARCHITECTURE

Opcode

Mod R/M

BX

or

BP

or

SI or

DI

EA

A1017-0A

Figure 2-14. Register Indirect Addressing

Opcode

Mod R/M

Displacement

BX

or

BP

+

EA

A1018-0A

Figure 2-15. Based Addressing

Based addressing provides a simple way to address data structures that may be located in different places in memory (see Figure 2-16). A base register can be pointed at the structure. Elements of the structure can then be addressed by their displacements. Different copies of the same structure can be accessed by simply changing the base register.

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Intel 80C188XL, 80C186XL user manual Register Indirect Addressing, Based Addressing