MC68LC040RC25A Datasheet, PDF (236/442 Pages) Freescale Semiconductor, Inc – M68040 Users Manual

Freescale Semiconductor, Inc.
8.4.4 Floating-Point Post-Instruction Stack Frame (Format $3)
The processor restores the SR and PC values from the stack and increments the active
supervisor stack pointer by $C. If another floating-point post-instruction exception is
pending, exception processing begins immediately for the new exception; otherwise, the
processor resumes normal instruction execution.
Stack Frames
15
0
SP
STATUS REGISTER
+$02
PROGRAM COUNTER
+$06
0011
VECTOR OFFSET
+$08
EFFECTIVE ADDRESS
FLOATING-POINT POST-INSTRUCTION
STACK FRAME–FORMAT $3
Exception Types
• Floating-Point Post-
Instruction
Stacked PC Points To
• Next Instruction: <ea> is the
calculated effective address
for the floating-point
instruction.
8.4.5 Eight-Word Stack Frame (Format $4)
The MC68040V, MC68LC040, MC68EC040, and MC68EC040V use this stack frame for
unimplemented floating-point instructions. The MC68040 does not generate or recognize
this format stack frame. Refer to Appendix A MC68LC040 and Appendix B MC68EC040
for further details about this stack frame.
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