dsp56800e Freescale Semiconductor, Inc, dsp56800e Datasheet - Page 684

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

B.3
A summary of condition code generation for every DSP56800E instruction appears in Table B-3 on
page B-9. Note that the condition code computations shown in Table B-3 may differ from those given in
the individual instruction descriptions in Appendix A, “Instruction Set Details.” In general, Table B-3
gives the core implementation viewpoint, while the instruction descriptions give the user viewpoint.
B.3.1
Table B-2 presents the notation that is used in Table B-3 on page B-9.
B.3.2
Table B-3 on page B-9 lists the computation for the condition code bits for each instruction, using the
notation that is outlined in Table B-2. Any unusual condition code calculation, or changes to bits in the
upper half of the status register, are noted in the “Comments” column.
B-8
Notation
*16
*32
*36
*xx
VT
=0
=1
—
*8
V
?
T
*
Condition Code Summary by Instruction
Notation
Condition Code Calculation Table
Set by the result of the operation according to the standard definition.
Not affected by the operation.
Set by the result of the operation according to the definition for 8-bit results in Section B.2, “Condition
Code Register.”
Set by the result of the operation according to the definition for 16-bit results in Section B.2, “Condition
Code Register.”
Set by the result of the operation according to the definition for 32-bit results in Section B.2, “Condition
Code Register.”
Set by the result of the operation according to the definition for 36-bit results in Section B.2, “Condition
Code Register.”
Set by the result of the operation according to the size of destination. This instruction can manipulate
operands that are of different sizes.
Cleared.
Set.
Set according to a special computation defined for the operation.
L bit is set if overflow has occurred in result.
L bit is set if limiting occurs when an accumulator is read during a parallel move or by the instruction
itself. An example of the latter case is
before performing the bit-manipulation operation.
L bit is set if overflow has occurred in result or if limiting occurs when an accumulator is read.
Table B-2. Condition Code Summary Table Notation
DSP56800E Core Reference Manual
BFCHG #$8000,A
Description
, which must first read the A accumulator
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