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Section 2 CPU
Rev. 4.00 Sep. 14, 2005 Page 45 of 982
REJ09B0023-0400
Table 2.5
Word Data Sign Extension
This LSI's CPU
Description
Example of Other CPU
MOV.W
@(disp,PC),R1
ADD R1,R0
........
.DATA.W H'1234
Sign-extended to 32 bits, R1
becomes H'00001234, and is then
operated on by the ADD instruction.
ADD.W #H'1234,R0
Note: Immediate data is referenced by @(disp,PC).
Load/Store Architecture: Basic operations are executed between registers. In operations
involving memory, data is first loaded into a register (load/store architecture). However, bit
manipulation instructions such as AND are executed directly on memory.
Delayed Branching: Unconditional branch instructions, etc., are executed as delayed branches.
With a delayed branch instruction, the branch is made after execution of the instruction (called the
slot instruction) immediately following the delayed branch instruction. This minimizes disruption
of the pipeline when a branch is made.
With a delayed branch, the actual branch operation occurs after execution of the slot instruction.
However, instruction execution for register updating, etc., excluding the branch operation, is
performed in delayed branch instruction
→
delay slot instruction order. For example, even though
the contents of the register holding the branch destination address are changed in the delay slot,
the branch destination address remains as the register contents prior to the change.
Table 2.6
Delayed Branch Instructions
This LSI's CPU
Description
Example of Other CPU
BRA TRGET
ADD R1,R0
ADD is executed before branch to
TRGET.
ADD.W R1,R0
BRA TRGET
Multiply/Multiply-and-Accumulate Operations: A 16
×
16
→
32 multiply operation is
executed in 1 to 2 states, and a 16
×
16 + 64
→
64 multiply-and-accumulate operation in 2 states.
A 32
×
32
→
64 multiply operation and a 32
×
32 + 64
→
64 multiply-and-accumulate operation
are each executed in 2 to 3 states.
T Bit: The result of a comparison is indicated by the T bit in the status register (SR), and a
conditional branch is performed according to whether the result is True or False. Processing speed
has been improved by keeping the number of instructions that modify the T bit to a minimum.
Summary of Contents for HD6417641
Page 2: ...Rev 4 00 Sep 14 2005 Page ii of l...
Page 7: ...Rev 4 00 Sep 14 2005 Page vii of l...
Page 11: ...Rev 4 00 Sep 14 2005 Page xi of l USB Universal serial bus WDT Watch dog timer...
Page 12: ...Rev 4 00 Sep 14 2005 Page xii of l...
Page 28: ...Rev 4 00 Sep 14 2005 Page xxviii of l...
Page 204: ...Section 4 Clock Pulse Generator CPG Rev 4 00 Sep 14 2005 Page 154 of 982 REJ09B0023 0400...
Page 212: ...Section 5 Watchdog Timer WDT Rev 4 00 Sep 14 2005 Page 162 of 982 REJ09B0023 0400...
Page 228: ...Section 6 Power Down Modes Rev 4 00 Sep 14 2005 Page 178 of 982 REJ09B0023 0400...
Page 246: ...Section 8 X Y Memory Rev 4 00 Sep 14 2005 Page 196 of 982 REJ09B0023 0400...
Page 318: ...Section 11 User Break Controller UBC Rev 4 00 Sep 14 2005 Page 268 of 982 REJ09B0023 0400...
Page 454: ...Section 12 Bus State Controller BSC Rev 4 00 Sep 14 2005 Page 404 of 982 REJ09B0023 0400...
Page 504: ...Section 14 U Memory Rev 4 00 Sep 14 2005 Page 454 of 982 REJ09B0023 0400...
Page 566: ...Section 17 Compare Match Timer CMT Rev 4 00 Sep 14 2005 Page 516 of 982 REJ09B0023 0400...
Page 868: ...Section 21 A D Converter Rev 4 00 Sep 14 2005 Page 818 of 982 REJ09B0023 0400...
Page 914: ...Section 23 I O Ports Rev 4 00 Sep 14 2005 Page 864 of 982 REJ09B0023 0400...
Page 956: ...Section 24 List of Registers Rev 4 00 Sep 14 2005 Page 906 of 982 REJ09B0023 0400...
Page 1016: ...Section 25 Electrical Characteristics Rev 4 00 Sep 14 2005 Page 966 of 982 REJ09B0023 0400...
Page 1024: ...Appendix Rev 4 00 Sep 14 2005 Page 974 of 982 REJ09B0023 0400...
Page 1032: ...Rev 4 00 Sep 14 2005 Page 982 of 982 REJ09B0023 0400 X X Y data addressing 52 X Y memory 193...
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