Analog Devices ADSP-BF535 Blackfin, Hardware Reference Manual

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ADSP-BF535 Blackfin Processor Hardware Reference 2-35
Computational Units
Saturating Multiplier Results on Overflow
These bits in
ASTAT
indicate multiplier overflow status:
• Bit 3 (
AV0
) and bit 4 (
AV1
) record overflow condition (whether the
result has overflowed 32 bits) for the
A0
and
A1
accumulators,
respectively.
If the bit is cleared (=0), no overflow or underflow has occurred. If
the bit is set (=1), an overflow or underflow has occurred.
Multiplier Instruction Summary
For information about assembly language syntax and the effect of multi-
plier instructions on the status flags, see Appendix A, “ADSP-BF535
Considerations”, in the
Blackfin Processor Programming Reference .
Multiplier Instruction Options
The following descriptions of multiplier instruction options provide an
overview. Not all options are available for all instructions. For informa-
tion about how to use these options with their respective instructions, see
Blackfin Processor Programming Reference.
default No option; input data is signed fraction.
(IS)
Input data operands are signed integer. No shift
correction is made.
(FU)
Input data operands are unsigned fraction. No shift
correction is made.
(IU)
Input data operands are unsigned integer. No shift
correction is made.