TMS320F datasheet(39/389 Pages) TI

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Data Memory

3-6

3.3

Data Memory

Data-memory space addresses up to 64K 16-bit words. Each ’C24x device

has three on-chip DARAM blocks: B0, B1, and B2. Block B0 is configurable as

either data memory or program memory. Blocks B1 and B2 are available for

data memory only.

Data memory can be addressed with either of two addressing modes: direct-

addressing or indirect-addressing. Addressing modes are described in detail

in Chapter 6.

When direct addressing is used, data memory is addressed in blocks of 128

words called data pages. The entire 64K of data memory consists of 512 data

pages labeled 0 through 511. The current data page is determined by the value

in the 9-bit data page pointer (DP) in status register ST0. Each of the 128 words

on the current page is referenced by a 7-bit offset, which is taken from the

instruction that is using direct addressing. Therefore, when an instruction uses

direct addressing, you must specify both the data page (with a preceding

instruction) and the offset (in the instruction that accesses data memory).

Figure 3–3. Pages of Data Memory

Data Memory

Page 0: 0000h–007Fh

Page 1: 0080h–00FFh

Page 2: 0100h–017Fh

Page 511: FF80h–FFFFh

000 0000

Offset

DP Value

0000 0000 0

111 1111

0000 0000 0

0000 0000 1

1111 1111 1

000 0000

111 1111

000 0000

111 1111

0000 0001 0

000 0000

111 1111

0000 0001 0

TMS320F Datasheet(PDF) 39 Page - Texas Instruments