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3  CONFIGURATION OF INSTRUCTIONS
3.5  Reducing Instruction Processing Time

Operation processing time can be reduced with standard device registers (Z).
The following shows an example program with standard device registers.

Operation processing time is reduced with the instructions that the subset processing is possible.
For the number of steps, refer to Page 119 Counting Step Number.
For the operation time for each instruction, refer to Page 883 Operation Processing Time.

Because standard device registers are the same devices as index registers, do not use device numbers of the 
standard device registers for the index registers.

Contact instructions

LD, LDI, AND, ANI, OR, ORI, LDP, LDF, ANDP, ANDF, ORP, ORF, LDPI, 
ANDPI, ANDFI, ORPI, ORFI

Output instructions

OUT, SET, RST

Comparison operation instructions

=, <>, <, <=, >, >=, D=, D<>, D<, D<=, D>, D>=

Arithmetic operation

+, -, *, /, INC, DEC, D+, D-, D*, D/, DINC, DDEC, B+, B-, B*, B/, E+, E-, E*, E/

Data conversion instructions

BCD, BIN, DBCD, DBIN, FLT, DFLT, INT, DINT

Data transfer instructions

MOV, DMOV, CML, DCML, XCH, DXCH, FMOV, BMOV, EMOV

Program branch instructions

CJ, SCJ, JMP

Logic operations

WAND, DAND, WOR, DOR, WXOR, DXOR, WXNR, DXNR

Rotation instructions

RCL, DRCL, RCR, DRCR, ROL, DROL, ROR, DROR

Shift instructions

SFL, DSFL, SFR, DSFR

Data processing instructions

SUM, SEG

Structure creation instructions

FOR, CALL

+ D0 D10 D20

+

Z0

Z1 Z2

Using data registers takes three steps and the operation processing time of
28.5 ns. (With the Q26UDEHCPU)

Using standard device registers instead of data registers takes one step and the
operation processing time of 9.5 ns. (With the Q26UDEHCPU)