SH7040 Datasheet, PDF (87/923 Pages) Renesas Technology Corp – Renesas 32-Bit Single-Chip RISC Microprocessor SuperH RISC engine Family/SH7040 Series(CPU Core SH-2)

Word or longword immediate data is not located in the instruction code, but instead is stored in a
memory table. An immediate data transfer instruction (MOV) accesses the memory table using the
PC relative addressing mode with displacement.
2.3 Instruction Features
2.3.1 RISC-Type Instruction Set
All instructions are RISC type. This section details their functions.
16-Bit Fixed Length: All instructions are 16 bits long, increasing program code efficiency.
One Instruction per Cycle: The microprocessor can execute basic instructions in one cycle using
the pipeline system. Instructions are executed in 35 ns at 28.7 MHz.
Data Length: Longword is the standard data length for all operations. Memory can be accessed in
bytes, words, or longwords. Byte or word data accessed from memory is sign-extended and
handled as longword data. Immediate data is sign-extended for arithmetic operations or zero-
extended for logic operations. It also is handled as longword data (table 2.2).
Table 2.2 Sign Extension of Word Data
SH7040 Series CPU
Description
MOV.W @(disp,PC),R1
ADD
R1,R0
.........
.DATA.W H'1234
Data is sign-extended to 32
bits, and R1 becomes
H'00001234. It is next
operated upon by an ADD
instruction.
Note: @(disp, PC) accesses the immediate data.
Example of Conventional CPU
ADD.W #H'1234,R0
Load-Store Architecture: Basic operations are executed between registers. For operations that
involve memory access, data is loaded to the registers and executed (load-store architecture).
Instructions such as AND that manipulate bits, however, are executed directly in memory.
Delayed Branch Instructions: Unconditional branch instructions are delayed. Executing the
instruction that follows the branch instruction and then branching reduces pipeline disruption
during branching (table 2.3). There are two types of conditional branch instructions: delayed
branch instructions and ordinary branch instructions.
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