MC68030 Datasheet, PDF (403/602 Pages) Motorola, Inc – ENHANCED 32-BIT MICROPROCESSOR

Coprocessor Interface Description
10.4.9 Evaluate Effective Address and Transfer Data Primitive
The evaluate effective address and transfer data primitive transfers an operand between the
coprocessor and the effective address specified in the coprocessor instruction operation
word. This primitive applies to general category instructions. If the coprocessor issues this
primitive during the execution of a conditional category instruction, the main processor
initiates protocol violation exception processing. Figure 10-29 shows the format of the
evaluate effective address and transfer data primitive.
15
14 13 12 11 10
87
0
CA
PC DR
1
0
VALID EA
LENGTH
Figure 10-29. Evaluate Effective Address and Transfer Data Primitive
This primitive uses the CA, PC, and DR bits as previously described.
The valid effective address field (bits [8-10]) of the primitive format specifies the valid
effective address categories for this primitive. If the effective address specified in the
instruction operation word is not a member of the class specified by bits [8-10], the main
processor aborts the coprocessor instruction by writing an abort mask (refer to 10.3.2
Control CIR) to the control CIR and by initiating F-line emulation exception processing.
Table 10-4 lists the valid effective address field encodings.
Table 10-4. Valid EffectiveAddress Codes
Field
000
001
010
011
100
101
110
111
Category
Control Alterable
Data Alterable
Memory Alterable
Alterable
Control
Data
Memory
Any Effective Address
(No Restriction)
MOTOROLA
MC68030 USER’S MANUAL
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