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TDC: Difference between revisions

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(good way to zero accumulator)
 
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'''TDC''' (Transfer Direct page register to aCcumulator) is a [[65c816]] instruction that transfers the value of the [[direct page register]] to the 16-bit [[accumulator]].  An alternate mnemonic is "TDA."
'''TDC''' (Transfer Direct page register to aCcumulator) is a [[65c816]] instruction that transfers the value of the [[direct page register]] to the 16-bit [[accumulator]].  An alternate mnemonic is "TDA."


TDC works even in [[6502 emulation mode]].
TDC ignores the [[m flag]] and always transfers 16 bits, even in [[6502 emulation mode]].


==== Syntax ====
==== Syntax ====
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TDA
TDA
</pre>
</pre>
TDC is a good way to zero the [[accumulator]], but only works when the direct page has not be relocated, of course.


=== See Also ===
=== See Also ===

Latest revision as of 00:30, 10 August 2024

Basic Info
Addressing Mode Opcode Length Speed
Implied (type 1) 7B 1 byte 2 cycles
Flags Affected
N V M X D I Z C
N . . . . . Z .

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

TDC ignores the m flag and always transfers 16 bits, even in 6502 emulation mode.

Syntax

TDC
TDA

TDC is a good way to zero the accumulator, but only works when the direct page has not be relocated, of course.

See Also

External Links