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Stack Pointer: Difference between revisions
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1FFh is a common value to initialize the stack pointer to. | 1FFh is a common value to initialize the stack pointer to. | ||
Pushing things onto the [[stack]] decrements the stack pointer and pulling things increments it. | |||
=== See Also === | === See Also === | ||
Revision as of 04:07, 9 August 2024
The Stack Pointer (SP) on the SPC700 is 16-bit, but the upper byte is fixed by the hardware to be 0x01.
On the 65c816, the only two instructions that modify the stack pointer (S) directly are TCS and TXS.[4] It is only fixed to be in page one in emulation mode on the '816.
1FFh is a common value to initialize the stack pointer to.
Pushing things onto the stack decrements the stack pointer and pulling things increments it.
See Also
References
- subparagraph 8.1.5 of page 3-8-4 of Book I of the official Super Nintendo development manual
- diversified activities: page 3-8-5 of Book I, lbid.
- Eyes & Lichty, page 31
- Eyes & Lichty, page 511 on TCS