
6
268
6.1
Instruction queue buffer
Calculation number of cycles
Sample program
Address Code Instruction
FC058 64 JMP TEST_11
FC059 04 NOP
FC05A 04 NOP
FC05B 04 NOP
FC05C 04 NOP
FC05D 04 NOP
FC05E TEST_11:
FC05E 73F10040 MOV.W 04000h, R1
FC062 64 JMP TEST_12
FC063 04 NOP
FC064 04 NOP
FC065 04 NOP
FC066 04 NOP
FC067 04 NOP
FC068 TEST_12:
Content at jump address is
prefetched at the same time
the instruction queue buffer is
cleared.
Fetch code
64
73F1 64
JMP TEST_11 MOV.W JMP TEST_12
Instructions
under execution
Instruction
queue buffer
04 04
73
73 00 0404 04
04 04 04
73
F1 F1 40 04 04 04
0464000404
04 0404
7373
F1 F1
40
00
WR
PPPP P
Address bus
Data bus (H)
Data bus (L)
RD
DR : Indicates a data read.
FC05A FC05E
04000
73 00
04
F1 40
FC060
FC06A
BCLK
: Indicates the locations of the instruction queue buffer that are cleared.
Fetch
Content at jump address is
prefetched at the same time
the instruction queue buffer
is cleared.
Jump address
40
04
64
04
64
64
73
00
F1
40
FC068
0040
04
04
04
04
AA
AA
04
04
FC062 FC064
PDR
P : Indicates a prefetch (reading from memory into the instruction queue buffer).
Address from which to read data
Fetch
Fetch
Content at address 400116
Content at address 400016
Sample program
Address Code Instruction
FC062 64 JMP TEST_11
FC063 04 NOP
FC064 04 NOP
FC065 04 NOP
FC066 04 NOP
FC067 04 NOP
FC068 TEST_11:
FC068 73F10140 MOV.W 04001h, R1
FC06C 64 JMP TEST_12
FC06D 04 NOP
FC06E 04 NOP
FC06F 04 NOP
FC070 04 NOP
FC071 04 NOP
FC072 TEST_12:
Fetch code
64
73F1 64
JMP TEST_11 MOV.W JMP TEST_12
Instructions
under execution
Instruction
queue buffer
04 04
73
73 00 0404 04
04 04 04
73
F1 F1 40 04 04 04
0464010404
04 0404
7373
F1 F1
40
00
WR
PPPP P
Address bus
Data bus (H)
Data bus (L)
RD
DR : Indicates a data read.
FC064 FC068 04001
73 00
04
F1 40
FC06A
FC074
BCLK
: Indicates the locations of the instruction queue buffer that are cleared.
Jump address
40 04
64
04
64
64
73
00
F1
40
FC072
0040
04
04
04
04
AA
04
04
FC06C
FC06E
DRDR
P : Indicates a prefetch (reading from memory into the instruction queue buffer).
Low-order address from
which to read data
64
04
04002
AA
Read from even
address
P
Content at address 4001
16
Content at address 4002
16
Fetch
Fetch
Fetch
Content at jump address is
prefetched at the same time
the instruction queue buffer
is cleared.
Content at jump address is
prefetched at the same time
the instruction queue buffer
is cleared.
High-order address from
which to read data
Figure 6.1.3. When executing an instruction to read from even addresses starting from an even address
(Program area: 16-bit bus without wait state; Data area: 16-bit bus without wait state)
Figure 6.1.4. When executing an instruction to read from odd addresses starting from an even address
(Program area: 16-bit bus without wait state; Data area: 16-bit bus without wait state)
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