beautypg.com

Ldb [%ir]+,%ba, Ldb [%x]+,imm8 – Epson S1C63000 User Manual

Page 114

background image

108

EPSON

S1C63000 CORE CPU MANUAL

CHAPTER 4: INSTRUCTION SET

LDB [%ir]+,%BA

Load BA reg. into location [ir reg.] and increment ir reg.

2 cycles

Function:

[ir]

A, [ir + 1]

B, ir

ir + 2

Loads the content of the BA register into the data memory. The content of the A register is
loaded into the data memory addressed by the ir register (X or Y) as the low-order 4 bits, and
the content of the B register is loaded into the next address as the high-order 4 bits. The ir
register (X or Y) is incremented by 2 words.

Code:

Mnemonic

MSB

LSB

LDB [%X]+,%BA

1

1

1

1

1

1

1

0

1

1

0

0

1

1FD9H

LDB [%Y]+,%BA

1

1

1

1

1

1

1

0

1

1

0

1

1

1FDBH

Flags:

E

I

C

Z

Mode:

Src: Register direct
Dst: Register indirect
Extended addressing: Invalid

LDB [%X]+,imm8

Load immediate data imm8 into location [X reg.] and increment X reg. 2 cycles

Function:

[X]

i3-0, [X+1]

i7-4, X

X + 2

Loads the 8-bit immediate data imm8 into the data memory. The low-order 4 bit-data is loaded
into the data memory addressed by the ir register (X or Y), and the high-order 4-bit data is
loaded into the next address. The ir register (X or Y) is incremented by 2 words.

Code:

Mnemonic

MSB

LSB

LDB [%X]+,imm8

0

0

0

0

1 i7 i6 i5 i4 i3 i2 i1 i0

0100H–01FFH

Flags:

E

I

C

Z

Mode:

Src: Immediate data
Dst: Register indirect
Extended addressing: Invalid