CHAPTER 4: INSTRUCTION SET

SBC [%ir]+,%r

Subtract with carry r reg. from location [ir reg.] and increment ir reg. 2 cycles

Function: [ir] ←

[ir] - r - C, ir ←

 

ir + 1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subtracts the content of the r register (A or B) and carry (C) from the data memory addressed

 

by the ir register (X or Y). Then increments the ir register (X or Y). The flags change due to the

 

operation result of the data memory and the increment result of the ir register does not affect

 

the flags.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Code:

Mnemonic

 

MSB

 

 

 

 

 

 

 

 

 

 

LSB

 

 

 

SBC [%X]+,%A

 

1

 

1

0

0

0

1

1

1

0

1

0

0

 

1

18E9H

 

 

SBC [%X]+,%B

 

1

 

1

0

0

0

1

1

1

0

1

1

0

 

1

18EDH

 

 

SBC [%Y]+,%A

 

1

 

1

0

0

0

1

1

1

0

1

0

1

 

1

18EBH

 

 

SBC [%Y]+,%B

 

1

 

1

0

0

0

1

1

1

0

1

1

1

 

1

18EFH

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Flags:

E

 

I

C

 

 

Z

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

↓

 

–

↕

 

 

 

↕

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Mode:

Src: Register direct

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Dst: Register indirect

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Extended addressing: Invalid

 

 

 

 

 

 

 

 

 

 

 

 

 

SBC [%ir],imm4

Subtract with carry immediate data imm4 from location [ir reg.] 2 cycles

Function: [ir] ←

[ir] - imm4 - C

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subtracts the 4-bit immediate data imm4 and carry (C) from the data memory addressed by the

 

ir register (X or Y).

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Code:

Mnemonic

 

MSB

 

 

 

 

 

 

 

 

 

 

LSB

 

 

 

SBC [%X],imm4

 

1

 

1

0

0

0

1

0

0

0

i3

i2

i1

i0

1880H–188FH

 

 

SBC [%Y],imm4

 

1

 

1

0

0

0

1

0

1

0

i3

i2

i1

i0

18A0H–18AFH

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Flags:

E

 

I

C

 

 

Z

 

 

 

 

 

 

 

 

 

 

 

 

 

 

↓

 

–

↕

 

 

 

↕

 

 

 

 

 

 

 

 

 

 

 

 

 

Mode:

Src: Immediate data

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Dst: Register indirect

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Extended addressing: Valid

 

 

 

 

 

 

 

 

 

 

 

 

 

Extended

LDB

 

%EXT,imm8

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

operation: SBC

[%X],imm4

 

[00imm8] ←

[00imm8] - imm4 - C (00imm8 = 0000H + 00H to FFH)

 

LDB

 

%EXT,imm8

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SBC

[%Y],imm4

 

[FFimm8] ←

[FFimm8] - imm4 - C (FFimm8 = FF00H + 00H to FFH)

126

EPSON

S1C63000 CORE CPU MANUAL