CPU Registers
2-7
Central Processing Unit
compare operations from 32-bit-wide data memory. It can also accept the
32-bit result of a multiplication operation.
The halves and quarters of the ACC can also be accessed (see Figure 2
ACC can be treated as two independent 16-bit registers: AH (high 16 bits) and
AL (low 16 bits). The bytes within AH and AL can also be accessed
independently. Special byte-move instructions load and store the most signifi-
cant byte or least significant byte of AH or AL. This enables efficient byte pack-
ing and unpacking.
Figure 2
−
3. Individually Accessible Portions of the Accumulator
ACC
AH
AL
AH.MSB
AH = ACC (31:16)
AH.MSB = ACC (31:24)
AH.LSB = ACC (23:16)
AH.LSB
AL.MSB
AL.LSB
AL = ACC (15:0)
AL.MSB = ACC (15:8)
AL.LSB = ACC (7:0)
The accumulator has the following associated status bits. For the details on
these bits, see section 2.3,
Status Register ST0
.
-
Overflow mode bit (OVM)
-
Sign-extension mode bit (SXM)
-
Test/control flag bit (TC)
-
Carry bit (C)
-
Zero flag bit (Z)
-
Negative flag bit (N)
-
Latched overflow flag bit (V)
-
Overflow counter bits (OVC)
Содержание TMS320C28x
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Страница 269: ...IN loc16 PA 6 112 MOV AL 0 AL 0 UOUT IORegC AL IOspace IORegC AL 10...
Страница 308: ...MAXCUL P loc32 6 151 Saturate MOVL Var64 2 ACC Store result into Var64 MOVL Var64 P...
Страница 509: ...SUBL ACC P PM 6 352 SUBL ACC P PM ACC S B 11 M X 4 MOVH Y ACC 5 Store Q15 result into Y...
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