Intel UPI- 41A, Руководство пользователя

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UPI-41A/41AH/42/42AH USER’S MANUAL
JF1 address Jump If C/D Flag (F1) Is Set
Opcode: 0 1 1 1 0 1 1 0
#
a
7
a
6
a
5
a
4
a
3
a
2
a
1
a
0
This is a 2-cycle instruction. Control passes to the specified address if the C/D flag (F
1
) is set
to one.
(PC
0–7
)
w
addr if F
1
e
1
Example: JF 1IS1: JF1 FILBUF ;JUMP TO ‘FILBUF’
;ROUTINE IF F
1
e
1
JMP address Direct Jump Within 1K Block
Opcode: a
10
a
9
a
8
0 0 1 0 0
#
a
7
a
6
a
5
a
4
a
3
a
2
a
1
a
0
This is a 2-cycle instruction. Bits 0 – 10 of the program counter are replaced with the directly-
specified address.
(PC
8–10
)
w
addr 8 – 10
(PC
0–7
)
w
addr 0 – 7
Example:
JMP SUBTOT ;JUMP TO SUBROUTINE ‘SUBTOT’
JMP $ – 6 ;JUMP TO INSTRUCTION SIX LOCATIONS
;BEFORE CURRENT LOCATION
JMP 2FH ;JUMP TO ADDRESS ‘2F’ HEX
JMPP @ A Indirect Jump Within Page
Opcode: 1 0 1 1 0 0 1 1
This is a 2-cycle instruction. The contents of the program memory location pointed to by the
accumulator are substituted for the ‘page’ portion of the program counter (PC 0 – 7).
(PC
0–7
)
w
((A))
Example: Assume accumulator contains OFH
JMPPAG: JMPP
@ A ;JMP TO ADDRESS STORED IN
;LOCATION 15 IN CURRENT PAGE
JNC address Jump If Carry Is Not Set
Opcode: 1 1 1 0 0 1 1 0 # a
7
a
6
a
5
a
4
a
3
a
2
a
1
a
0
This is a 2-cycle instruction. Control passes to the specified address if the carry bit is not set,
that is, equals zero.
(PC
0–7
)
w
addr if C
e
0
Example:
JC0: JNC NOVFLO ;JUMP TO ‘NOVFLO’ ROUTINE
;IF C
e
0
JNIBF address Jump If Input Buffer Full Flag Is Low
Opcode: 1 1 0 1 0 1 1 0
#
a
7
a
6
a
5
a
4
a
3
a
2
a
1
a
0
This is a 2-cycle instruction. Control passes to the specified address if the Input Buffer Full
flag is low (IBF
e
0).
(PC
0–7
)
w
addr if IBF
e
0
Example: LOC 3:JNIBF LOC 3 ;JUMP TO SELF IF IBF
e
0
;OTHERWISE CONTINUE
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