User Manual
C166S V2
Instruction Set
User Manual
7-192
V 1.7, 2001-01
7.3
Instruction Opcodes
This section lists the C166S V2 CPU instructions by hexadecimal opcodes to help
identify specific instructions when reading executable code, ie. during the debugging
phase.
Notes for Opcode Lists
• These instructions are encoded by means of additional bits in the operand field of the
instruction
x0
H
– x7
H
:
Rw, #data3
or
Rb, #data3
x8
H
– xB
H
:
Rw, [Rw]
or
Rb, [Rw]
xC
H
– xF
H
:
Rw, [Rw +]
or
Rb, [Rw +]
For these instructions, only the lowest four GPRs (R0 to R3) can be used as indirect
address pointers.
• These instructions are encoded by means of additional bits in the operand field of the
instruction
00xx.xxxx
B
:
EXTS
or
ATOMIC
01xx.xxxx
B
:
EXTP
10xx.xxxx
B
:
EXTSR
or
EXTR
11xx.xxxx
B
:
EXTPR
Notes on the JMPR Instructions
The condition code to be tested for the JMPR instructions is specified by the opcode.
Two mnemonic representation alternatives exist for some of the condition codes.
Notes on the JMPA and CALLA Instructions
For JMPA+/- and CALLA+/- instructions, a static user programmable prediction scheme
is used. If bit 8 (’a’) of the instruction long word is cleared, then the branch is assumed
‘taken’. If it is set, then the branch is assumed ‘not taken’. The user controls bit 8 value
by entering ’+’ or ’-’ in the instruction mnemonics. This bit can be also set/cleared by the
Assembler for JMPA and CALLA instructions depending on the jump condition.
For JMPA instruction, a pre-fetch hint bit is used (the instruction bit 9 ’l’). This bit is
required by the fetch unit to deal efficiently with short backward loops. It must be set if 0
< IP_jmpa - IP_target <= 32, where IP_jmpa is the address of the JMPA instruction and
IP_target is the target address of the JMPA. Otherwise, bit 9 must be cleared.
Notes on the BCLR and BSET Instructions
The position of the bit to be set or cleared is specified by the opcode. The operand
‘bitoff.n’ (n = 0 to 15) refers to a particular bit within a bit-addressable word.
Summary of Contents for C166S V2
Page 102: ...User Manual C166S V2 C166S V2 Memory Organization User Manual 3 102 V 1 7 2001 01...
Page 116: ...User Manual C166S V2 Instruction Pipeline User Manual 4 116 V 1 7 2001 01...
Page 152: ...User Manual C166S V2 Interrupt and Exception Handling User Manual 5 152 V 1 7 2001 01...
Page 204: ...User Manual C166S V2 Instruction Set User Manual 7 204 V 1 7 2001 01...
Page 420: ...User Manual C166S V2 Detailed Instruction Description User Manual 8 420 V 1 7 2001 01...
Page 432: ...User Manual C166S V2 Summary of CPU Subsystem Registers User Manual 9 432 V 1 7 2001 01...
Page 437: ...437...