A SERVICE OF

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INSTRUCTION SET
(PCO-7)~
addr
(PC) = (PC)+2
If
C=O
IF
C=1
Example:
JCO:
JNC
NOVFLO ;JUMP
TO
'NOVFLO' ROUTINE
;If
C=O
JNI
address
Jump If Interrupt Input
is
Low
(Not in 8021, 8022)
11
0 0 0 1 0 1 1 0 I 1
a7
a6
as
a4
I
a3 a2
a1
ao
I
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
If
1=0
(PC) = (PC)+2 If
1=1
Example: LOC
3:
JNI
EXTINT ;JUMP TO 'EXTINT' ROUTINE
;If
1=0
JNTO
address
Jump If Test 0
Is
Low
(Not in 8021)
1 0 0 1 0 1 0 1 1 0 1 1
a7
a6
as
a4
1
a3 a2
a1
ao
I
This is a 2-cycle instruction. Control passes
to
the
specified address,
if
the test 0 signal is
low
(PCO-7)~
addr
(PC) = (PC)+2
Example: JTOLOW: JNTO
60
If
TO=O
If
TO=1
;JUMP
TO
LOCATION
60
DEC
;IF
TO=O
JNT1
address
Jump If Test 1
Is
Low
This is a 2-cycle instruction. Control passes
to
the
specified address,
if
the test 1 signal is low.
(PCO-7)~
addr
If
T1=0
(PC) = (PC)+2
If
T1=1
JNZ
address
Jump If Accumulator
Is
Not Zero
11
0 0 1 1 0 1 1 0 1 1
a7
a6
as
a4
1
a3 a2
a1
ao
I
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.
(PCO-7)~
addr
(PC) = (PC)+2
Example: JACCNO:
JNZ
OABH
Mnemonics copyright Intel Corporation
1976.
If
A"tO
If
A=O
;JUMP
TO
LOCATION
'AB' HEX
;IF ACC VALUE IS NONZERO
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