2 Computational Units
2 – 4
2.1.8
Summary
Table 2.1 summarizes some of the arithmetic characteristics of ADSP-2100
family operations. In addition to the numeric types described in this
section, the ADSP-2100 Family C Compiler supports a form of 32-bit
floating-point in which one 16-bit word is the exponent and the other
word is the mantissa. See the ADSP-2100 Family C Tools Manual.
O
PERATION
A
RITHMETIC
F
ORMATS
ALU
Operands
Result
Addition
Signed or unsigned
Interpret flags
Subtraction
Signed or unsigned
Interpret flags
Logical Operations
Binary string
same as operands
Division
Explicitly signed/unsigned
same as operands
ALU Overflow
Signed
same as operands
ALU Carry Bit
16-bit unsigned
same as operands
ALU Saturation
Signed
same as operands
MAC, Fractional
Multiplication (P)
1.15 Explicitly signed/unsigned
32 bits (2.30)
Multiplication (MR)
1.15 Explicitly signed/unsigned
2.30 shifted to 1.31
Mult / Add
1.15 Explicitly signed/unsigned
2.30 shifted to 1.31
Mult / Subtract
1.15 Explicitly signed/unsigned
2.30 shifted to 1.31
MAC Saturation
Signed
same as operands
MAC, Integer Mode
Multiplication (P)
1.15 Explicitly signed/unsigned
32 bits (2.30)
Multiplication (MR)
16.0 Explicitly signed/unsigned
32.0 no shift
Mult / Add
16.0 Explicitly signed/unsigned
32.0 no shift
Mult / Subtract
16.0 Explicitly signed/unsigned
32.0 no shift
MAC Saturation
Signed
same as operands
Shifter
Logical Shift
Unsigned / binary string
same as operands
Arithmetic Shift
Signed
same as operands
Exponent Detection
Signed
same as operands
Table 2.1 Arithmetic Formats