upd75238 Renesas Electronics Corporation., upd75238 Datasheet - Page 152

• Manufacturer Part Number: upd75238
• Description: 4 Bit Single-chip Microcomputer
• Manufacturer: Renesas Electronics Corporation.

152
(3) String effect instructions
(4) Base conversion instruction
When two or more instructions in the same group (group A or B) are placed at two or more string effect
addresses, the instruction placed at the start point of the string effect instructions is executed. After that,
each string effect instruction is executed as an NOP instruction.
Group A: MOV A, #n4,
Group B: MOV HL, #n8
The PD75238 is provided with base conversion instructions to convert the results of addition and
subtraction of 4-bit data to a base-n number.
When a base-m number is to be obtained, the following combinations of instructions are used for
adjustment.
• For addition
• For subtraction SUBC A, @HL
The result of adding or subtracting the contents of the accumulator and the memory addressed by the
HL register pair is converted to a base-m number. However, for subtraction, the complement of the
obtained result (base-m number) is set in the accumulator. An overflow or underflow is reflected in the
carry flag. (In the above combinations, the skip function of the ADDS A, #m instruction is prohibited.)
ADDS A, #16-m
ADDC A, @HL
ADDS A, #m
ADDS A, #m
MOV XA, #n8
PD75238