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Motorola DSP96002 User Manual

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D-22

DSP96002 USER’S MANUAL

MOTOROLA

D.1.5.1.2.7

Data ALU Results/Move Compatibility Summary

Figure C-3 summarizes what happens when Data ALU operation results of a certain range is stored in the

destination register, and the register is read by a certain kind of move.

All cases where "move out type"=SP and "move out result"=WRONG can be corrected by rounding in the

instruction (using the .S option). The case where "move out type"=SP and "move out result"=TRUNC can

also be corrected by using the .S option.


ROUND EXPONENT RANGE DATA ALU OPERATION TAGS MOVE MOVE OUT
TO BEFORE ROUND RESULT OUT RESULT
(UNBIASED) U V TYPE

SP NaN operand or non signaling NaN (QNAN) 0 0 SP CORRECT
invalid op written as DP QNAN
e=7FF mantissa=1.11...11 DP CORRECT

SP 127 written as DP infinity
e=7FF mantissa=1.00...00 DP CORRECT

SP 127
DP CORRECT

SP -150

<

e

< −

126 denormalized (in SP) 1 0 SP CORRECT


DP WRONG

SP e

< −

149 zero (underflow) 0 0 SP CORRECT


DP CORRECT

SEP NaN operand or non signaling NaN (QNAN) 0 0 SP CORRECT
invalid op written as DP QNAN
e=7FF mantissa=1.11...11 DP CORRECT

SEP 1023 written as DP infinity
e=7FF mantissa=1.00...00 DP CORRECT

SEP 127 normalized in SEP
DP CORRECT

SEP -127
DP CORRECT

Figure C -3. Data ALU Results/Move Compatibility Summary (Continued)