Memory Interface

Table 2-26 describes the data representation for each 64-bit row in Figure 2-21.

Table 2-26. Data Representation in Memory

Representation Type

Value

 

 

 

 

 

 

Eight 8-bit bytes

A0

= $0a, A1 = $0b, A2 = $0c, A3 = $0d, A4 = $0e, A5 = $0f

 

 

 

Four 16-bit numbers

A8

= $0102, A10 = $0304, A12 = $0506, A14 = $0708

 

 

Two 32-bit numbers

A16 = $11223344, A20 = $ccddeeff

 

 

 

2.4.1.3 Data Moves

Data moves are executed by moving core registers to and from memory over one of the data buses (XDBA or XDBB).

The data registers can be accessed with three types of data:

Long type access, writing or reading 32-bit operands.

Word type access, writing or reading 16-bit operands.

Byte type access, writing or reading 8-bit operands.

Figure 2-22 shows an example of data transfer in big and little endian modes.

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SC140 DSP Core Reference Manual

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Freescale Semiconductor SC140 specifications Data Moves, Data Representation in Memory, Representation Type Value