What is the function of the extra coprocessor register of the MRC command?

Quote from ARM documentation MRC,

MRC{2}<c><q> <coproc>, #<opc1>, <Rt>, <CRn>, <CRm>{, #<opc2>}

Where:

2If specified, selects T2 / A2 encoding. If omitted, selects the encoding T1 / A1.

<c><q>See Standard Assembly Syntax Fields on page A8-7. ARM MRC2 instruction must be unconditional.

<coproc>The name of the coprocessor. The standard names for common coprocessors are p0, p1, ..., p15.

<opc1> Indicates the code of operation with the coprocessor in the range from 0 to 7.

<Rt>Is the register of the primary destination ARM address. This register can be R0-R14 or APSR_nzcv. The last form writes bits [31:28] of the transferred value to the status flags N, Z, C and V and is set by setting the encoding field Rt to 0b1111. In the pre-UAL assembler syntax, instead of APSR_nzcv, a PC was written instead of a PC.

<CRn> , .

<CRm> .

<opc2> , , 0 7. , <opc2> 0.

MRC ARM, CRm? , , opcode, .

+1
1

user786653, , .

, fpu, fpa, , fpa, , , (mrc/mcr).

: , , , , . ARM , , . , , TRM, , TRM ( , ARM), , , - elses, , , , . , , , . mrc/mcr , , Google, , - , / undefined , .

, mrc/mcr , , , . FPA, , /, . ARM. TRM , , .

+3

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