SEH – Set Half Carry Flag

Operation:

(i)

H ← 1

Syntax:

Operands:

Program Counter:

(i)

SEH

None

PC ← PC + 1

16-bit Opcode:

1001

0100

0101

1000

Status Register (SREG) and Boolean Formula:

I

T

H

S

V

N

Z

C

–

–

1

–

–

–

–

–

seh

; Set Half Carry Flag

Operation:

(i)

I ← 1

Syntax:

Operands:

Program Counter:

(i)

SEI

None

PC ← PC + 1

16-bit Opcode:

1001

0100

0111

1000

Status Register (SREG) and Boolean Formula:

I

T

H

S

V

N

Z

C

1

–

–

–

–

–

–

–

sei

; set global

interrupt

enable

sleep

;

enter sleep, waiting

for interrupt

;

note: will

enter sleep before any pending interrupt(s)

Words:

1 (2 bytes)

Cycles:

1

Operation:

(i)

N ← 1

Syntax:

Operands:

Program Counter:

(i)

SEN

None

PC ← PC + 1

16-bit Opcode:

1001

0100

0010

1000

Status Register (SREG) and Boolean Formula:

I

T

H

S

V

N

Z

C

–

–

–

–

–

1

–

–

add

r2,r19

;

Add

r19 to r2

sen

;

Set

Negative Flag

Operation:

(i)

Rd ← $FF

Syntax:

Operands:

Program Counter:

(i)

SER Rd

16 ≤ d ≤ 31

PC ← PC + 1

16-bit Opcode:

1110

1111

dddd

1111

Status Register (SREG) and Boolean Formula:

I

T

H

S

V

N

Z

C

–

–

–

–

–

–

–

–

Example:

clr

r16

; Clear r16

ser

r17

; Set r17

out

$18,r16

; Write zeros to Port B

nop

; Delay (do nothing)

out

$18,r17

; Write ones to Port B