Talk:CPU addressing modes: Difference between revisions
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(Created page with "For (d),y adressing, shouldn't the formula be: PEEK(PEEK(arg) + (PEEK((arg + 1) % 256) * 256) + y) instead of PEEK(PEEK(arg) + PEEK((arg + 1) % 256) + y) ?") |
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== (d),y addressing typo == | |||
For (d),y adressing, shouldn't the formula be: | For (d),y adressing, shouldn't the formula be: | ||
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? | ? | ||
<small><span class="autosigned">— Preceding unsigned comment added by [[User:135.23.206.197|135.23.206.197]] ([[User talk:135.23.206.197|talk]] • [[Special:Contributions/135.23.206.197|contribs]]) </span></small><!-- Template:Unsigned --> | |||
:Yes. Amended. - [[User:Rainwarrior|Rainwarrior]] ([[User talk:Rainwarrior|talk]]) 15:39, 9 February 2016 (MST) | |||
== Phrasing doesn't match table == | |||
The line: | |||
"The (d''')''',y mode is used far more often than (d,x)." | |||
Should be modified to match the declaration pattern in the proceeding table, as follows: | |||
"The (d,y''')''' mode is used far more often than (d,x)." --SirGouki | |||
: There is no (d,y) mode. —[[User:Lidnariq|Lidnariq]] ([[User talk:Lidnariq|talk]]) 11:48, 22 April 2021 (MDT) | |||
:: To clarify, there are two different addressing modes which perform indexing and indirection: one performs indexing first and indirection second (and uses the X register), and the other performs indirection first and indexing second (and uses the Y register). The first one effectively lets you use an array of pointers to individual bytes (which isn't very useful), but the second one is equivalent to having a single pointer to a 256-byte array (which is '''extremely''' useful). Furthermore, the table doesn't say "(d,y)" as you claim, but says "(d),y" as it should. --[[User:Quietust|Quietust]] ([[User talk:Quietust|talk]]) 06:58, 23 April 2021 (MDT) | |||
Latest revision as of 12:58, 23 April 2021
(d),y addressing typo
For (d),y adressing, shouldn't the formula be:
PEEK(PEEK(arg) + (PEEK((arg + 1) % 256) * 256) + y)
instead of
PEEK(PEEK(arg) + PEEK((arg + 1) % 256) + y)
?
— Preceding unsigned comment added by 135.23.206.197 (talk • contribs)
- Yes. Amended. - Rainwarrior (talk) 15:39, 9 February 2016 (MST)
Phrasing doesn't match table
The line:
"The (d),y mode is used far more often than (d,x)."
Should be modified to match the declaration pattern in the proceeding table, as follows:
"The (d,y) mode is used far more often than (d,x)." --SirGouki
- There is no (d,y) mode. —Lidnariq (talk) 11:48, 22 April 2021 (MDT)
- To clarify, there are two different addressing modes which perform indexing and indirection: one performs indexing first and indirection second (and uses the X register), and the other performs indirection first and indexing second (and uses the Y register). The first one effectively lets you use an array of pointers to individual bytes (which isn't very useful), but the second one is equivalent to having a single pointer to a 256-byte array (which is extremely useful). Furthermore, the table doesn't say "(d,y)" as you claim, but says "(d),y" as it should. --Quietust (talk) 06:58, 23 April 2021 (MDT)
