User manual

37
Double Word Addressing
Double word addressing is same with word addressing, except that
32-bit data is referenced by the specified address and its next address.
The type of instruction used determines which addressing, word or
double word addressing, is applied. For comparison instructions, the
programmer must be in “Double Mode” to enter a double-word
comparison. For other instructions, those instructions that start with a
D in front of the related word instruction are double word instructions,
and the data is processed as double words
Example 1:
The value of D or S of the instruction can process data from 0 to 4,294,967,295.
Example 2:
Range when double word instructions are used
Word
Double
word
D=W0
S=7000
LET
D=W0
S=70000
DLET
W0 is processed as 16-bit (1 word) data.
(0 to 65, 355)
S is processed from 0 to 65,535.
Double word W0 is composed of W0 and W1.
W0 is LSB. W1 is located in MSB.
W0000 is
MO
M1
M2
M3
M1
M0
M2
2
31
2
30
... 2
17
2
16
2
15
2
14
... 2
1
2
06
15 14 ... 1 1 15 14 ... 1 0
W0000W0001