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Store Y Index In Memory
Opcode: STY
Operation: Y → M
Status Register: Status-List.png

STY (Store Y Index In Memory) stores the Y index into a specified memory address. It is similar in function to STA and STY.


This pseudo C code shows how the STY opcode functions when it is executed.

STORE(Operand, Y);   // Stores the Y Index Register into the memory address specified in the operand.

Addressing Modes

Addressing Mode Assembly Language Form Opcode # Bytes # Cycles
Zero Page STY Operand 84 2 3
Zero Page, X STY Operand, X 94 2 4
Absolute STY Operand 8C 3 4