SUB (Super FX): Difference between revisions

Latest revision as of 19:14, 30 July 2024


Basic Info
Addressing Mode	Opcode	Length	ROM Speed	RAM Speed	Cache Speed
Implied (type 1)	6n	1 byte	3 cycles	3 cycles	1 cycle
Immediate	3E6n	2 bytes	6 cycles	6 cycles	2 cycle


Flags Affected
B	ALT1	ALT2	O/V	S	CY	Z
0	0	0	O/V	S	CY	Z

SUB is a Super FX instruction that performs a subtraction between the source register and an operand. The difference is stored in the destination register. The subtrahend may be any register from R₀ to R₁₅ or any immediate value from 0 to 15. The source register is the minuend.

The ALT0 state is restored.

The source and destination registers should be specified in advance using WITH, FROM, or TO. Otherwise, R₀ serves as the default.

If an unsigned borrow occurred, CY is set, otherwise it is cleared.

Syntax

SUB Rn
SUB #n

Example 1

Let:

S_reg : R₅
D_reg : R₄
R₅ = 735ah
R₈ = 426bh

After executing SUB R₈:

R₄ = 30efh

Example 2

Let:

S_reg : R₀
D_reg : R₀
R₀ = 329bh

After executing SUB #10:

R₀ = 3291h

External Links

Official Nintendo documentation on SUB: 9.86 on page 2-9-118 of Book II
SUB with immediate addressing: 9.87 on page 2-9-119 of Book II

@@ Line 1: / Line 1: @@
-'''SUB''' is a [[Super FX]] instruction that performs a subtraction.
+{| class="wikitable" style="float:right;clear:right;width:50%"
+!colspan="8"|Basic Info
+|+
+|'''Addressing Mode'''
+|'''Opcode'''
+|'''Length'''
+|'''ROM Speed'''
+|'''RAM Speed'''
+|'''Cache Speed'''
+|+
+|[[Implied]] (type 1)
+|6n
+|1 byte
+|3 cycles
+|3 cycles
+|1 cycle
+|+
+|[[Immediate]]
+|3E6n
+|2 bytes
+|6 cycles
+|6 cycles
+|2 cycle
+|}
 {| class="wikitable" style="float:right;clear:right;width:30%"
-!colspan="9"|Flags Clobbered
+!colspan="9"|Flags Affected
 |+
-|B
+|[[B Flag|B]]
-|ALT1
+|[[ALT1]]
-|ALT2
+|[[ALT2]]
+|[[O/V]]
+|[[Sign Flag|S]]
+|[[CY]]
+|[[Zero Flag|Z]]
+|+
+|0
+|0
+|0
 |O/V
 |S
 |CY
 |Z
-|+
-|0
-|0
-|0
-|
-|
-|
-|
 |}
+'''SUB''' is a [[Super FX]] instruction that performs a subtraction between the [[source register]] and an operand.  The difference is stored in the [[destination register]].  The subtrahend may be any register from R<sub>0</sub> to R<sub>15</sub> or any immediate value from 0 to 15.  The source register is the minuend.
+The [[ALT0]] state is restored.
+The source and destination registers should be specified in advance using [[WITH]], [[FROM]], or [[TO]].  Otherwise, R<sub>0</sub> serves as the default.
+If an unsigned borrow occurred, [[CY]] is set, otherwise it is cleared.
+==== Syntax ====
+<pre>
+SUB Rn
+SUB #n
+</pre>
+==== Example 1 ====
+Let:
+ S<sub>reg</sub> : R<sub>5</sub>
+ D<sub>reg</sub> : R<sub>4</sub>
+ R<sub>5</sub> = 735ah
+ R<sub>8</sub> = 426bh
+After executing SUB R<sub>8</sub>:
+ R<sub>4</sub> = 30efh
+==== Example 2 ====
+Let:
+ S<sub>reg</sub> : R<sub>0</sub>
+ D<sub>reg</sub> : R<sub>0</sub>
+ R<sub>0</sub> = 329bh
+After executing SUB #10:
+ R<sub>0</sub> = 3291h
+=== See Also ===
+* [[ADD]]
+* [[ADC (Super FX)]]
+* [[ADC]]
+* [[CMP (Super FX)]]
+* [[SBC (Super FX)]]
+* [[ALT2]]
+=== External Links ===
+* Official Nintendo documentation on SUB: 9.86 on [https://archive.org/details/SNESDevManual/book2/page/n274 page 2-9-118 of Book II]
+* SUB with immediate addressing: 9.87 on [https://archive.org/details/SNESDevManual/book2/page/n275 page 2-9-119 of Book II]
 [[Category:ASM]]
-[[Category:Enhancement Chips]]
+[[Category:Super FX]]
+[[Category:Arithmetic Operation Instructions]]
+[[Category:One-byte Instructions]]
+[[Category:Expects Sreg/Dreg Prearranged]]