We've just updated MediaWiki and its underlying software. If anything doesn't look or work quite right, please mention it to us. --RanAS
Stack: Difference between revisions
From SnesLab
(more nonexistent instructions) |
(top of stack ref) |
||
Line 5: | Line 5: | ||
In [[emulation mode]] it wraps within page one.<sup>[2]</sup> | In [[emulation mode]] it wraps within page one.<sup>[2]</sup> | ||
The stack grows towards zero, but the most recently pushed byte is nontheless called the top of the stack. These instructions push things to the stack: | The stack grows towards zero, but the most recently pushed byte is nontheless called the top of the stack.<sup>[4]</sup> These instructions push things to the stack: | ||
* [[PEA]] | * [[PEA]] | ||
Line 43: | Line 43: | ||
# Clark, Bruce. http://www.6502.org/tutorials/65c816opcodes.html#5.1.1 | # Clark, Bruce. http://www.6502.org/tutorials/65c816opcodes.html#5.1.1 | ||
# section 2.11 of 65c816 datasheet: https://www.westerndesigncenter.com/wdc/documentation/w65c816s.pdf | # section 2.11 of 65c816 datasheet: https://www.westerndesigncenter.com/wdc/documentation/w65c816s.pdf | ||
# [[Eyes & Lichty]], [https://archive.org/details/0893037893ProgrammingThe65816/page/33 page 33] | |||
[[Category:ASM]] | [[Category:ASM]] | ||
[[Category:Inherited from 6502]] | [[Category:Inherited from 6502]] | ||
[[Category:Buffers]] | [[Category:Buffers]] |
Revision as of 23:51, 16 August 2024
The Stack is a buffer which remembers the state of subroutines that are currently executing.
On the 65c816, the stack is always in bank zero.[3] It can be thousands of bytes deep.[1]
In emulation mode it wraps within page one.[2]
The stack grows towards zero, but the most recently pushed byte is nontheless called the top of the stack.[4] These instructions push things to the stack:
PL* instructions take one cycle more than their PH* counterparts. These instructions pull things from the stack:
Note the lack of PLK. PHS and PLS similarly do not exist, nor do any instructions performing the inverse of PEA, PEI, or PER.
See Also
References
- Wilson, Garth. https://wilsonminesco.com/816myths
- Clark, Bruce. http://www.6502.org/tutorials/65c816opcodes.html#5.1.1
- section 2.11 of 65c816 datasheet: https://www.westerndesigncenter.com/wdc/documentation/w65c816s.pdf
- Eyes & Lichty, page 33