UPD75238GJ NEC [NEC], UPD75238GJ Datasheet - Page 153

• Manufacturer Part Number: UPD75238GJ
• Description: 4 BIT SINGLE-CHIP MICROCOMPUTER
• Manufacturer: NEC [NEC]

8.2 INSTRUCTION SET AND ITS OPERATION
(1) Representation format and description method of operands
An operand is described in the operand field of each instruction according to the description method
corresponding to the operand representation format of the instruction. Refer to the assembler specifi-
cations for details. When two or more elements are described in the description method field, select one
of them. Uppercase letters, a plus sign (+), and a minus sign (-) are keywords, so they can be used without
alteration.
Specify an appropriate numeric value or label for immediate data.
The symbols shown in format diagrams in Chapters 3 to 5 can be used as a label instead of mem, fmem,
pmem, and bit. However, there are some restrictions on usable labels for fmem and pmem. (See (2) in
Section 8.1.)
Note Only even addresses can be specified for 8-bit data processing.
Representa-
tion format
reg
reg1
rp
rp1
rp2
rp’
rp’1
rpa
rpa1
n4
n8
mem
bit
fmem
pmem
addr1
addr
caddr
faddr
taddr
PORTn
IE
RBn
MBn
X, A, B, C, D, E, H, L
X, B, C, D, E, H, L
XA, BC, DE, HL
BC, DE, HL
BC, DE
XA, BC, DE, HL, XA’, BC’, DE’, HL’
BC, DE, HL, XA’, BC’, DE’, HL’
HL, HL+, HL-, DE, DL
DE, DL
4-bit immediate data or label
8-bit immediate data or label
8-bit immediate data or label
2-bit immediate data or label
FB0H-FBFH/FF0H-FFFH immediate data or label
FC0H-FFFH immediate data or label
0000H-7F7FH immediate data or label
0000H-3F7FH immediate data or label
12-bit immediate data or label
11-bit immediate data or label
20H-7FH immediate data (bit 0 = 0) or label
PORT0-PORT15
IEBT, IECSI0, IET0, IETPG, IE0, IE1, IE2, IEKS, IEW, IE4
RB0-RB3
MB0, MB1, MB2, MB3, MB15
Description method
Note
PD75238
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