Difference between revisions of "Undocumented SDBD Behavior"

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m (Protected "Undocumented SDBD Behavior" ([edit=autoconfirmed] (indefinite) [move=autoconfirmed] (indefinite)))
(No difference)

Latest revision as of 09:45, 4 December 2010


Need to put here:

  • SDBD + indirect through R6: Seem to recall results in two stack reads from top of stack, and ultimately decrements stack pointer once.
  • SDBD + indirect while using same register as register argument. (e.g. SDBD; ADD@ R4, R4) CPU uses an interesting blend of old, new register values.
  • SDBD + direct: Need to dig up Carl Jr's description of the CPU's behavior here. It's an interesting blend of Direct and Indirect access modes.