AVR Instruction Set Nomenclature: Status Register (SREG ...
AVR Instruction Set Nomenclature: Status Register (SREG ...
AVR Instruction Set Nomenclature: Status Register (SREG ...
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SEI - <strong>Set</strong> Global Interrupt Flag<br />
Description:<br />
<strong>Set</strong>s the Global Interrupt flag (I) in <strong>SREG</strong> (status register).<br />
Operation:<br />
(i) I ← 1<br />
Syntax: Operands: Program Counter:<br />
(i) SEI None PC ← PC + 1<br />
112<br />
16-bit Opcode:<br />
<strong>Status</strong> <strong>Register</strong> (<strong>SREG</strong>) and Boolean Formula:<br />
I: 1<br />
Global Interrupt flag set<br />
Example:<br />
1001 0100 0111 1000<br />
I T H S V N Z C<br />
1 - - - - - - -<br />
Words: 1 (2 bytes)<br />
Cycles: 1<br />
cli ; Disable interrupts<br />
in r13,$16 ; Read Port B<br />
sei ; Enable interrupts<br />
<strong>Instruction</strong> <strong>Set</strong>