Datasheet
Section 2 CPU 
R01UH0310EJ0500 Rev. 5.00    Page 65 of 1384 
Sep 25, 2012     
H8S/2426, H8S/2426R, H8S/2424 Group 
Table 2.4  Arithmetic Operations Instructions (1) 
Instruction Size* Function 
ADD 
SUB 
B/W/L  Rd ± Rs → Rd, Rd ± #IMM → Rd 
Performs addition or subtraction on data in two general registers, or on 
immediate data and data in a general register. (Immediate byte data 
cannot be subtracted from byte data in a general register. Use the 
SUBX or ADD instruction.) 
ADDX 
SUBX 
B  Rd ± Rs ± C → Rd, Rd ± #IMM ± C → Rd 
Performs addition or subtraction with carry or borrow on byte data in two 
general registers, or on immediate data and data in a general register. 
INC 
DEC 
B/W/L  Rd ± 1 → Rd, Rd ± 2 → Rd 
Increments or decrements a general register by 1 or 2. (Byte operands 
can be incremented or decremented by 1 only.) 
ADDS 
SUBS 
L  Rd ± 1 → Rd, Rd ± 2 → Rd, Rd ± 4 → Rd 
Adds or subtracts the value 1, 2, or 4 to or from data in a 32-bit register. 
DAA 
DAS 
B  Rd (decimal adjust) → Rd 
Decimal-adjusts an addition or subtraction result in a general register by 
referring to the CCR to produce 4-bit BCD data. 
MULXU B/W Rd × Rs → Rd 
Performs unsigned multiplication on data in two general registers: 
either 8 bits × 8 bits → 16 bits or 16 bits × 16 bits → 32 bits. 
MULXS B/W Rd × Rs → Rd 
Performs signed multiplication on data in two general registers: 
either 8 bits × 8 bits → 16 bits or 16 bits × 16 bits → 32 bits. 
DIVXU  B/W  Rd ÷ Rs → Rd 
Performs unsigned division on data in two general registers: 
either 16 bits ÷ 8 bits → 8-bit quotient and 8-bit remainder or 
32 bits ÷ 16 bits → 16-bit quotient and 16-bit remainder. 
Note:  *  Size refers to the operand size. 
 B:  Byte 
    W: Word 
 L:  Longword 










