Specifications

largest . . . . . . . . . . . . . . . . . . . . . . . . . . . 077777
077776
positive
.
.
.
000001
000000
177777
177776
negative
lQo00l
smallest
100000
whereas in unsigned 16-bit arithmetic the sequence is considered to be .
highest . . . . ~ . . . . . . . . . . . . . . . . . . . . . . . . . 177777
.
000002
00000 1
lowest _. .._. . . . _.. ._ ,. ._ __, 000000
Branch on Less ThadZero)
BLT lot
l.Sir. 2.6~
01 0
I I I II I I I I I I I
2 4
offset
15 8 7 0
Operation: lot + (PC) if N V V = 1
Description: Causes a branch if the “Exclusive OR” of the N- and V-bits are’
1. Thus BLT will always branch following an operation that added two neg
ative numbers, even if overflow occurred.
In particular, BLT will always cause a branch if it follows a CMP instruction
operating on a negative source and a positive destination (even if overfloti
occurred). Further, BLT will never cause a branch when it follows a CMP
instruction operating on a positive source and negative destination. BLT
will not cause a branch if the result .of the previous operation was zero
(without overflow).
Branch on Greater than or Equal (Zero)
BGE lot
1.5 rrs.2.6~~
0 1 0
I I 2, IO
offset
I
I I I I I
15
8 7
0
Operation: lot + (PC) if N V V = 0
Description: Causes a branch if N and V are either both clear or both set.
BGE is .the complementary operation to BLT. Thus BGE will always cause
a branch when it follows an operation that caused addition to two positive
numbers. BGE will also cause a branch on a zero result.
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