Addressing modes, Chapter 6 – Texas Instruments TMS320C2XX User Manual

Page 137

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6-1

Addressing Modes

Addressing Modes

This chapter explains the three basic memory addressing modes used by the
’C2xx instruction set. The three modes are:

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Immediate addressing mode

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Direct addressing mode

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Indirect addressing mode

In immediate addressing, a constant to be manipulated by the instruction is
supplied directly as an operand of that instruction. Two types of immediate
addressing are available—short and long. In short-immediate addressing, an
8-, 9-, or 13-bit operand is included in the instruction word. Long-immediate
addressing uses a 16-bit operand.

When you need to access data memory, you can use direct or indirect addres-
sing. Direct addressing concatenates seven bits of the instruction word with
the nine bits of the data-memory page pointer (DP) to form the 16-bit data
memory address. Indirect addressing accesses data memory through one of
eight 16-bit auxiliary registers.

Topic

Page

6.1

Immediate Addressing Mode

6-2

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6.2

Direct Addressing Mode

6-4

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6.3

Indirect Addressing Mode

6-9

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Chapter 6

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