Exception Stack Frame - Motorola MC68030 User Manual

even be dynamically relocated for each task that is executed by an operating
system. Details of exception processing are provided in SECTION 8 EXCEP-
TION PROCESSING, and Table 8-1 lists the exception vector assignments.
4.3.2 Exception Stack Frame
/
Exception processing saves the most volatile portion of the current processor
context on the top of the supervisor stack. This context is organized in a
format called the exception stack frame. This information always includes a
copy of the status register, the program counter, the vector offset of the
vector, and the frame format field. The frame format field identifies the type
of stack frame. The RTE instruction uses the value in the format field to
properly restore the information stored in the stack frame and to deallocate
the stack space. The general form of the exception stack frame is illustrated
in Figure 4-1. Refer to SECTION 8 EXCEPTION PROCESSING for a complete
list of exception stack frames.
15 12
SP
---..
STATUS REGISTER
PROGRAM COUNTER
FORMAT
I VECTOR OFFSET
ADDITIDNAL PROCESSOR STATE INFORMATION
(2. 6. 12. OR 42 WORDS. IF NEEDED)
Figure 4-1. General Exception Stack Frame
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MC68030 USER'S MANUAL 4-7