Intel 8080 - B1_Page_53

Chapter 2. Assembly Language Concepts
Remember tlut number, arc absolutc terms. Thlh the expression RELOC
is not.
I ()O i, legal, but 100 RELOC
When two relocatable symbols have both been defined with the ,dme type oj reiocaLlbility, they m,lY appedr in
cerLlin expressiollS that yield an dbsulutl' result. Symbols have the '>dme type of rclocltability when both Ml'
rcLltive to the CSEG locdtion counter, both die reldtive to the DSEG luclli()n counter, both <lrc reldtivc to
MEMORY, or both arc relative to STACK. The following cxpressions arc valid and produce absolute results:
RELOCl .- RELOC2
r EQ
1
LT
RELOCl LE RELOC2
GT
GE
NE
Relocatdble symbols may not appear in expressions with any other operdtors.
The following
list shows dll pmsible combinations of operators with absolute and relocatable terms. An A in the
table indicdtes that the resulting dddress is absolute; an R indicdtes d relocatable address; an I indicates an
illegdl combination. Notice that only one term may dppear with the laq five operators in the list.
I Op"'!o>
X dbsolutc X absul u te
X relucaUble X relocatable
Y dbsolutc Y reloclldblc
Y absolute Y I"Clocatdblc
Y
A R
R
I
X +
X Y A
I
R A
X
*
Y
A I
I I
X
/
Y
A
I
I I
I
X MOD Y A
I
I I
I
X SHL
Y
A
I
I I
,
X SHR Y A
I
I
I
X
EQ Y A
I
I
A
X LT Y A
I
I
A
X LE Y A I
I
A
X GT Y A
I
I
A
X GE Y A
I
I
A
X NE
Y
A
I
I
A
X AND Y
A I
I I
X OR
Y
A I
I I
X XOR Y A
I
I
I
NOT
X
A
I
Hl(:;H
X
A
R
LOW
X
A
R
unary+
X
A
R
undrY X
A
I
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