Intel mcs-48 manual JF1 address Jump If Flag 1 Is Set Not in 8021, Jmpp @A Indirect Jump Within

INSTRUCTION SET

JF1 address Jump If Flag 1 Is Set (Not in 8021, 8022)

10 1 1 1 10 1 1 0 1 1a7 a6 as a4 1a3 a2 a1 ao 1

This is a 2-cycle instruction. Control passes to the specified address if flag 1 is set to one.

(PCO-7)"- addr	If F1 =1
(PC) = (PC)+2	IF F1=0
Example: JF1IS1: JF1 FILBUF	;JUMP TO 'FILBUF'
	;ROUTINE IF F1=1

JMP address Direct Jump Within 2K Block

Ia10 ag as 0 I0 1 0 0 1 Ia7 a6 as a4 1a3 a2 a1 ao 1

This is a 2-cycle instruction. Bits 0-10 of the program counter are replaced with the directly-specified address. The setting of PC bit 11 is determined by the most recent SELECT MB instruction.

(PCS-10)-- addr 8-10 (PCO-7)"- addr 0-7 (PC 11 )-- DBF

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

11011100111

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 bits 0-7).

(PCO-7)"- ((A))

Example: Assume accumulator contains OFH.

JMPPAG: JMPP @A	;JUMP TO ADDRESS STORED IN
	;LOCATION 15 IN CURRENT PAGE

JNC address Jump If Carry Is Not Set

11 1 1 0 10 1 1 0 1 Ia7 a6 as a4 1a3 a2 a1 ao I·

This is a 2-cycle instruction. Control passes to the specified address if the carry bit is not set, that is, equals zero.

Mnemonics copyright Intel Corporation 1976.

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