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6. Status Register (SREG)

The Status Register contains flags that indicate the results of arithmetic/logic operations. This register is crucial for branch instructions.

Bit Name Description
7 I (Global Interrupt Enable) Enables/disables global interrupts
6 T (Bit Copy Storage) Storage for BLD/BST instructions
5 H (Half Carry Flag) Carry from bit 3 to bit 4 (for BCD)
4 S (Sign Flag) S = N ⊕ V (for signed operations)
3 V (Overflow Flag) Two's complement overflow
2 N (Negative Flag) Result is negative (bit 7 = 1)
1 Z (Zero Flag) Result = 0
0 C (Carry Flag) Carry/borrow from operation