Intel MCS48 User Manual page 102

INSTRUCTION SET
(PC
_7)-*-
addr
(PC) = (PC)+2
If
c=o
IF
C=1
Example:
JCO:
JNC NOVFLO
;JUMP
TO
'NOVFLO'
ROUTINE
;lf
C=0
J Nl
address
Jump
If
Interrupt
Input
is
Low
(Not
in
8021, 8022)
1000
110
a
7
a 6 a
5
a 4 a 3 82 a! a
This
is
a 2-cycle
instruction.
Control passes
to the
specified
address
if
the
interrupt input signal
is
low
(=0),
that
is,
an
external interrupt
has
been
signaled. (This signal
initiates
an
interrupt
service
sequence
if
the external
interrupt
is
enabled.)
(PCo-7)^- addr
(PC) = (PC)+2
If
l=0
If
1
=
1
Example:
LOC
3:
JNI
EXTINT
JNT0
address
Jump
If
Test
Is
Low
(Not
in
8021)
;JUMP
TO
'EXTINT
ROUTINE
;lf
l=0
00 10
110
a
7
a
6
a
5
a 4
a
3
a
2
a-|
a
This
is
a 2-cycle
instruction.
Control passes
to
the
specified address,
if
the
test
signal
is
low
(PC
-7)-*-addr
(PC) = (PC)+2
If
T0=0
If
T0=1
Example:
JT0LOW: JNT0
60
JNT1
address
Jump
If
Test
1 Is
Low
;JUMP
TO LOCATION
60
DEC
;IF
T0=0
100 110
a
7
a 6 a 5 a 4
a 3 a
2
a-|
a
This
is
a 2-cycle
instruction.
Control passes
to
the
specified address,
if
the
test
1
signal
is
low.
(PCo-7)-«-
addr
(PC) =
(PC)+2
If
T1=0
If
T1=1
JNZ
address
Jump
If
Accumulator
Is
Not Zero
100
1
110
a
7
a
6
a
5
a
4
a 3 a
2
a-j
a
This
is
a 2-cycle
instruction.
Control
pases
to
the
specified
address
if
the
accumulator contents
are
nonzero
at
the time
this
instruction
is
executed.
(PC -7)^- addr
(PC) =
(PC)+2
Example:
JACCN0: JNZ
0ABH
Mnemonics
copyright
Intel
Corporation 1976.
If
A*0
If
A=0
;JUMP
TO
LOCATION
'AB'
HEX
;IF
ACC
VALUE
IS
NONZERO
4-20