dsp56800e Freescale Semiconductor, Inc, dsp56800e Datasheet - Page 233

• Manufacturer Part Number: dsp56800e
• Description: 16-bit Digital Signal Controller Core
• Manufacturer: Freescale Semiconductor, Inc

The basic operations performed are:
Example 7-4 presents an example of an instruction that performs this operation.
7.2.3
The bit-manipulation unit can perform logical operations on selected bits in an operand. The instructions
that perform these operations, in addition to performing the testing that is described in Section 7.1.3,
“16-Bit Testing Logic,” process selected bits in the original 16-bit source using the 16-bit logic unit and
write the results back to their original source. This operation is performed by the following instructions:
The basic operations performed are:
Note that these three steps are a non-interruptible sequence because they are implemented within a single
bit-manipulation instruction.
Example 7-5 presents an example of an instruction that performs this operation.
7.3
With the use of the following four operations, the bit-manipulation unit gives the DSP56800E core the
capability to perform logical operations with immediate data:
The operations ANDC, EORC, ORC, and NOTC are not instructions; they are aliases to the
bit-manipulation instructions that are identified in the preceding list. See Section 4.2.1, “The ANDC,
EORC, ORC, and NOTC Aliases,” on page 4-11 for additional information.
Freescale Semiconductor
1. Perform steps 1 through 5 in Section 7.2.1, “Testing Bits.”
2. Branch to the specified target address if the result of the test performed is True. Otherwise,
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1. Perform steps 1 through 5 in Section 7.2.1, “Testing Bits.”
2. Invert, clear, or set all bits selected by the 16-bit mask.
3. Write this modified result back to the 16-bit source operand.
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continue program execution with the next sequential instruction.
BFCHG
BFCLR
BFSET
ANDC—logically AND a 16-bit immediate value with an operand
EORC—logically exclusive OR a 16-bit immediate value with an operand
ORC—logically OR a 16-bit immediate value with an operand
NOTC—take the logical one’s-complement of a 16-bit destination
ANDC, EORC, ORC, and NOTC
Modifying Selected Bits
BRSET
BFCLR
#$8000,X:(R0),LABEL4
#$FF00,X:(R0)
Example 7-4. Branching on Bits in an Operand
Example 7-5. Clearing Bits in an Operand
Bit-Manipulation Unit
; Branch to LABEL4 if MSB set in X:(Rn)
; Clear upper byte of memory location
ANDC, EORC, ORC, and NOTC
7-5