Z80:Opcodes:JR - Revision history

ReGuess: /* T-States */

2017-03-19T18:31:17Z

T-States

← Older revision		Revision as of 18:31, 19 March 2017
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	<!-- What the instruction can be used for -->		<!-- What the instruction can be used for -->
	== T-States ==		== T-States ==
	cc is condition: NZ, Z, NC, C, PO, PE, P, M		cc is condition: NZ, Z, NC, C (PO, PE, P, M are not available)
	{\| class="wikitable"		{\| class="wikitable"
	\| X \|\| 12		\| X \|\| 12

ReGuess: /* Syntax */ This is the Syntax for JR, not JP. Also, contition.

2017-03-10T16:54:51Z

Syntax: This is the Syntax for JR, not JP. Also, contition.

← Older revision		Revision as of 16:54, 10 March 2017
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	<!-- Syntax for this instruction -->		<!-- Syntax for this instruction -->

	JP NN ;unconditional jump		JR NN ;unconditional jump
	JP cond.,NN ;conditional jump		JR cond.,NN ;conditional jump

	=== Allowed Instructions ===		=== Allowed Instructions ===
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	;Constants		;Constants
	JP NN ;no ~~contition~~		JR NN ;no condition
	JR C,NN ;jumps if C is set		JR C,NN ;jumps if C is set
	JR NC,NN ;jumps if C is reset		JR NC,NN ;jumps if C is reset

Maintenance script: Initial automated import

2016-02-05T22:24:31Z

Initial automated import

New page

Relative jumps to the address. This means that it can only jump between 128 bytes ahead or behind. Can be conditional or unconditional. JR takes up one less byte than [[Z80:Opcodes:JP|JP]], but is also slower. Weigh the needs of the code at the time before choosing one over the other (speed vs. size).

== Syntax ==



JP NN ;unconditional jump
JP cond.,NN ;conditional jump

=== Allowed Instructions ===



;Constants
JP NN ;no contition
JR C,NN ;jumps if C is set
JR NC,NN ;jumps if C is reset
JR Z,NN ;jumps if Z is set
JR NZ,NN ;jumps if Z is reset

== Effects ==


All flags preserved.

== Uses ==


== T-States ==
cc is condition: NZ, Z, NC, C, PO, PE, P, M
{| class="wikitable"
| X || 12
|}

{| class="wikitable"
| || condition met || condition not met
|-
| cc,X || 12 || 7
|}

== See Also ==


[[Z80:Opcodes:BIT|BIT]],[[Z80:Opcodes:CALL|CALL]],[[Z80:Opcodes:CP|CP]],[[Z80:Opcodes:CPD|CPD]],[[Z80:Opcodes:CPDR|CPDR]],[[Z80:Opcodes:CPI|CPI]],[[Z80:Opcodes:CPIR|CPIR]],[[Z80:Opcodes:DJNZ|DJNZ]],[[Z80:Opcodes:JP|JP]]

{{lowercase}}
[[Category:Z80 Assembly]]
[[Category:Z80 Heaven]]
[[Category:Z80 Opcodes]]