UPD75238GJ 查看數據表（PDF） - NEC => Renesas Technology

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UPD75238GJ

4 BIT SINGLE-CHIP MICROCOMPUTER

NEC => Renesas Technology 

µPD75238

Table 2-1 Addressing Modes

Addressing mode

Representation

format

Specified address

1-bit direct addressing

mem.bit

Bit specified by bit at the address specified by MB and mem. In this case:

When MBE = 0 and mem = 00H-7FH, MB = 0

When MBE = 0 and mem = 80H-FFH, MB = 15

When MBE = 1, MB = MBS

4-bit direct addressing

mem

Address specified by MB and mem. In this case:

When MBE = 0 and mem = 00H-7FH, MB = 0

When MBE = 0 and mem = 80H-FFH, MB = 15

When MBE = 1, MB = MBS

8-bit direct addressing

Address specified by MB and mem (mem: even address). In this case:

When MBE = 0 and mem = 00H-7FH, MB = 0

When MBE = 0 and mem = 80H-FFH, MB = 15

When MBE = 1, MB = MBS

4-bit register indirect

addressing

@HL

@HL+

@HL–

Address specified by MB and HL. In this case, MB = MBE• MBS

Address specified by MB and HL. In this case, MB = MBE• MBS.

HL+ automatically increments the L register after addressing.

HL- automatically decrements the L register after addressing.

@DE

Address specified by DE in memory bank 0

@DL

Address specified by DL in memory bank 0

8-bit register indirect

addressing

@HL

Address specified by MB and HL.

In this case, MB = MBE• MBS. Bit 0 of the L resister is ignored.

Bit manipulation

addressing

fmem.bit

Bit specified by bit at the address specified by fmem. In this case:

fmem = FB0H-FBFH (interrupt-related hardware)

fmem = FF0H-FFFH (I/O port)

pmem.@L

Bit specified by the low-order 2 bits of the L register at the address specified

by the high-order 10 bits of pmem and the high-order 2 bits of the L register.

In this case, pmem = FC0H-FFFH

@H+mem.bit Bit specified by bit at the address specified by MB, H, and the low-order 4 bits

of mem.

In this case, MB = MBE• MBS

Stack addressing

–

Address specified by SP in memory bank 0, 1, 2, and 3 selected by SBS

As summarized in Table 2-1, the µPD75238 allows both direct and indirect addressing in data memory

manipulation for 1-bit data, 4-bit data, and 8-bit data, so that very efficient and simple programming can be

performed.

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