Altera Nios II User Manual page 261

Chapter 8: Instruction Set Reference
Instruction Set Reference
rdctl
Operation:
Assembler Syntax:
Example:
Description:
Exceptions:
Instruction Type:
Instruction Fields:
31 30 29 28 27 26 25
0
February 2014 Altera Corporation
rC ← ctlN
rdctl rC, ctlN
rdctl r3, ctl31
Reads the value contained in control register ctlN and writes it to register rC.
Supervisor-only instruction
R
C = Register index of operand rC
N = Control register index of operand ctlN
24 23 22 21 20 19 18 17
0 C
16 15 14 13 12 11 10 9
0x26
read from control register
8 7 6 5 4 3 2
N 0x3a
Nios II Processor Reference Handbook
8–81
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