Motorola DSP96002 - Manual (Page 751)

C-28 DSP96002 USER’S MANUAL MOTOROLA
Exponent Comparator/Update Unit
11 Bits
11 Bits 11 Bits
11 Bits
ES1 ES2
max(E1, E2) E1-E2
To Mantissa
Alignment To Post-
Normalization
can only be used in long (L) data memory space.
3. Unsigned Word Integer: 32 bits wide with unsigned magnitude representation. This storage for-
mat can be used in either X and/or Y data memory space.
4. Unsigned Long Word Integer: 64 bits wide with unsigned magnitude representation. This stor-
age format can only be used in long (L) data memory space.
Long type integers can be moved to and from the data ALU register file. However, long integers can not be
directly used as input operands to data ALU operations. Long integers can however be results of data ALU
operations.
C.2.3 Integer Storage Format in the Data ALU
There are thirty 32-bit registers in which can contain integer words. However, data ALU arithmetic opera-
tions use the low portion of the register files as word source and destination operands. Long word integers
are only generated as results of integer arithmetic operations and are never used as source operands.
C.2.4 Integer Arithmetic
The integer arithmetic operations use the same arithmetic units in the data ALU as the floating point oper-
ations. These units consist of:
1. Adder: The subtract unit in the adder/subtracter unit described in paragraph C.1.5.3 is used for
integer add and subtract operations. It accepts two 32-bit integer operands from the low por-
tions of the data ALU source registers and delivers a 32-bit result in the low portion of the des-