Freescale Semiconductor MC68881 - Transfer Single Main Processor Register Primitive Format; Coprocessor Valid Effective Address Codes; Evaluate Effective Address and Transfer Data Primitive Encoding

7
Table 7-4. Coprocessor Valid Effective
Address Codes
000
Control Alterable
001 Data Alterable
010 Memory Alterable
011 Alterable
100
101
110
111
Control
Data
Memory
Any Effective Address
Table 7-5. Evaluate Effective Address and Transfer Data
Primitive Encoding
Valid
Usage CA PC DR <ea> Length
F<op><ea>,FPn (OPCLASS 010)
Issued as the first primitive of an instruction dialog to request the transfer 1 * 0 101 1
of an operand from memory or a main processor data register to the 1 * 0 101 2
FPCP. The length field indicates the size of the operand: byte, word, long ** * 0 101 4
or single, double, extended, or packed BCD. ** * 0 110 8
• *
* 0 110 12
FMOVE FPm,<ea> (OPCLASS 011}
Issued after the conversion from the internal extended precision format 1 0 1 001 1
to the destination format is completed to request the transfer of an op- 1 0 1 001 2
erand from the FPCP to memory or a main processor data register. The ** 0 1 001 4
length field indicates the size of the operand: byte, word, long or single, ** 0 1 010 8
double, extended, or packed BCD. ** 0 1 010 12
FMOVE <ea>,FPcr and FMOVEM <ea>,FPcr_list (OPCLASS 100)
Issued as the first primitive of an instruction dialog to request the transfer 1 0 0 111 4
of one or more control registers from memory or a main processor reg- 1 0 0 101 4
ister to the FPCP. The length field indicates the total size of all control 1 0 0 110 8
registers to be moved, 4 bytes per register. 1 0 0 110 12
FMOVE FPcr,<ea> and FMOVEM FPcr_list,<ea> (OPCLASS 101)
Issued as the first primitive of an instruction dialog to request the transfer 1 0 1 011 4
of one or more control registers from the FPCP to memory or a main 1 0 1 001 4
processor register. The length field indicates the total size of all control 1 0 1 010 8
registers to be moved, 4 bytes per register. 1 0 1 010 12
*PC = I if any arithmetic exceptions are enabled; otherwise PC=0.
**CA= 0 for some MC68882 instructions with S,D,X instruction operand formats;
otherwise, CA= 1.
7.4.2.3 TRANSFER SINGLE MAIN PROCESSOR REGISTER PRIMITIVE. This primitive is
used by the FPCP to request the transfer of one main processor register. The format of
this primitive is shown in Figure 7-10. The main processor services this request by writing
a long word to the operand CIR.
15 14 13 12 11 ]O 9 8 7 6 5 4 3 2 1 0
' ' ° ol o o o ° I°"1
Figure 7-10. Transfer Single Main Processor Register Primitive Format
FREESCALE
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MC68881/MC68882 USER'S MANUAL