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Absolute Boolean Bit Addressing: Difference between revisions

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'''13-bit Absolute Addressing''' is used on the [[SPC700]] by some instructions to address individual bits:
'''Absolute Boolean Bit''' is used on the [[SPC700]] by some three-byte instructions to address individual bits:


* [[AND1]]
* [[AND1]]
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The bottom 13 bits of a 16-bit value specify an absolute address, while the top 3 bits specify which bit within the byte stored at that address.  The greatest address these instructions can affect is 1FFFh.
The bottom 13 bits of a 16-bit value specify an absolute address, while the top 3 bits specify which bit within the byte stored at that address.  The greatest address these instructions can affect is 1FFFh.
==== Syntax ====
<pre>
AND1 C, mem. bit
AND1 C, /mem. bit
OR1 C, mem. bit
OR1 C, /mem. bit
EOR1 C, mem. bit
MOV1 C, mem. bit
MOV1 mem. bit, C
NOT1 mem. bit
</pre>


=== See Also ===
=== See Also ===
* [[Absolute Addressing]]
* [[Absolute Addressing]]
* [[Direct Page Bit Addressing]]


=== Reference ===
=== References ===
* [https://archive.org/details/SNESDevManual/book1/page/n186 page 3-8-8 of Book I] of the official Super Nintendo development manual
* [https://archive.org/details/SNESDevManual/book1/page/n186 page 3-8-8 of Book I] of the official Super Nintendo development manual
* Figure 3-8-3 Memory Access Addressing Effective Address on [https://archive.org/details/SNESDevManual/book1/page/n187 page 3-8-9], lbid.


[[Category:ASM]]
[[Category:ASM]]
[[Category:Addressing Modes]]
[[Category:Addressing Modes]]
[[Category:Scene Slang]]
[[Category:Official Jargon]]

Latest revision as of 14:25, 1 August 2024

Absolute Boolean Bit is used on the SPC700 by some three-byte instructions to address individual bits:

The bottom 13 bits of a 16-bit value specify an absolute address, while the top 3 bits specify which bit within the byte stored at that address. The greatest address these instructions can affect is 1FFFh.

Syntax

AND1 C, mem. bit
AND1 C, /mem. bit
OR1 C, mem. bit
OR1 C, /mem. bit
EOR1 C, mem. bit
MOV1 C, mem. bit
MOV1 mem. bit, C
NOT1 mem. bit

See Also

References