CLR1 (SPC700): Difference between revisions

Latest revision as of 22:18, 13 July 2024


Basic Info
Addressing Mode	Opcode	Length	Speed
Direct Page Bit	12	2 bytes	4 cycles
Direct Page Bit	32	2 bytes	4 cycles
Direct Page Bit	52	2 bytes	4 cycles
Direct Page Bit	72	2 bytes	4 cycles
Direct Page Bit	92	2 bytes	4 cycles
Direct Page Bit	B2	2 bytes	4 cycles
Direct Page Bit	D2	2 bytes	4 cycles
Direct Page Bit	F2	2 bytes	4 cycles


Flags Affected
N	V	P	B	H	I	Z	C
.	.	.	.	.	.	.	.

CLR1 is an SPC700 command that clears a bit in a direct page byte. The byte following the opcode determines which byte. The most significant 3 bits of the opcode determines which bit within that byte. In Nintendo's manual, the high nybble of the opcode is called y.

No flags are affected.

Syntax

CLR1 dip. bit

External Links

Official Nintendo documentation on CLR1: Table C-18 in Appendix C-9 of Book I
subparagraph 8.2.3.1 of page 3-8-8, lbid.
anomie: https://github.com/yupferris/TasmShiz/blob/8fabc9764c33a7ae2520a76d80ed7220bb939f12/spc700.txt#L375

@@ Line 1: / Line 1: @@
-'''CLR1''' is an [[SPC700]] command that clears the [[direct page flag]].
+{| class="wikitable" style="float:right;clear:right;width:40%"
+!colspan="8"|Basic Info
+|+
+|'''Addressing Mode'''
+|'''Opcode'''
+|'''Length'''
+|'''Speed'''
+|+
+|[[Direct Page Bit Addressing | Direct Page Bit]]
+|12
+|2 bytes
+|4 cycles
+|+
+|[[Direct Page Bit Addressing | Direct Page Bit]]
+|32
+|2 bytes
+|4 cycles
+|+
+|[[Direct Page Bit Addressing | Direct Page Bit]]
+|52
+|2 bytes
+|4 cycles
+|+
+|[[Direct Page Bit Addressing | Direct Page Bit]]
+|72
+|2 bytes
+|4 cycles
+|+
+|[[Direct Page Bit Addressing | Direct Page Bit]]
+|92
+|2 bytes
+|4 cycles
+|+
+|[[Direct Page Bit Addressing | Direct Page Bit]]
+|B2
+|2 bytes
+|4 cycles
+|+
+|[[Direct Page Bit Addressing | Direct Page Bit]]
+|D2
+|2 bytes
+|4 cycles
+|+
+|[[Direct Page Bit Addressing | Direct Page Bit]]
+|F2
+|2 bytes
+|4 cycles
+|}
+{| class="wikitable" style="float:right;clear:right;width:30%"
+!colspan="8"|Flags Affected
+|+
+|[[Negative Flag|N]]
+|[[Overflow Flag|V]]
+|[[Direct Page Flag|P]]
+|[[Break Flag|B]]
+|[[Half-Carry Flag|H]]
+|[[Interrupt Enable Flag|I]]
+|[[Zero Flag|Z]]
+|[[Carry Flag|C]]
+|+
+|.
+|.
+|.
+|.
+|.
+|.
+|.
+|.
+|}
+'''CLR1''' is an [[SPC700]] command that clears a bit in a [[direct page]] byte.  The byte following the opcode determines which byte.  The most significant 3 bits of the opcode determines which bit within that byte.  In Nintendo's manual, the high nybble of the opcode is called y.
+No flags are affected.
+==== Syntax ====
+<pre>
+CLR1 dip. bit
+</pre>
+=== See Also ===
+* [[SET1]]
+* [[TCLR1]]
+* [[RMB]]
+* [[dip bit]]
+=== External Links ===
+* Official Nintendo documentation on CLR1: Table C-18 in [https://archive.org/details/SNESDevManual/book1/page/n234 Appendix C-9 of Book I]
+* subparagraph 8.2.3.1 of [https://archive.org/details/SNESDevManual/book1/page/n186 page 3-8-8], lbid.
+* anomie: https://github.com/yupferris/TasmShiz/blob/8fabc9764c33a7ae2520a76d80ed7220bb939f12/spc700.txt#L375
 [[Category:ASM]]
 [[Category:SPC700]]
 [[Category:Bit Operation Commands]]
+[[Category:Read-Modify-Write Instructions]]
+[[Category:Two-byte Instructions]]