TCD: Difference between revisions

Latest revision as of 02:57, 19 December 2023


Basic Info
Addressing Mode	Opcode	Length	Speed
Implied (type 1)	5B	1 byte	2 cycles


Flags Affected
N	V	M	X	D	I	Z	C
	.	.	.	.	.		.

TCD (Transfer aCcumulator to Direct page register) is a 65c816 instruction that transfers the value of the 16-bit accumulator to the direct page register. An alternate mnemonic is "TAD."

TCD ignores the M flag. If the accumulator is only 8 bits wide, the transfer still happens as if it were 16 bits wide.

TCD works even in 6502 emulation mode.

External Links

Eyes & Lichty page 510 on TCD: https://archive.org/details/0893037893ProgrammingThe65816/page/n536
Labiak page 191 on TCD: https://archive.org/details/Programming_the_65816/page/n201
snes9x implementation of TCD: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L2320

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 '''TCD''' (Transfer aCcumulator to Direct page register) is a [[65c816]] instruction that transfers the value of the 16-bit [[accumulator]] to the [[direct page register]].  An alternate mnemonic is "TAD."
+TCD ignores the M flag.  If the accumulator is only 8 bits wide, the transfer still happens as if it were 16 bits wide.
+TCD works even in [[6502 emulation mode]].
 === See Also ===
@@ Line 51: / Line 55: @@
 [[Category:Transfer Instructions]]
 [[Category:One-byte Instructions]]
+[[Category:Implied Instructions]]
+[[Category:Two-cycle Instructions]]