A 3-letter opcode for the 6502 processor. It is one of the most frequently used operation (second only to the LDA instruction). This opcode stores an 8-bit value, that is held by the Accumulator, somewhere in memory (RAM).

Back to the 6502 opcodes metanode

A 6502 instruction that stores register A at a given memory location.
  • Function: A => N
  • Updates flags: none
  • Opcode numbers:
    (d,x) $81
    dp    $85
    abs   $8D
    (d),y $91
    d,x   $95
    a,y   $99
    a,x   $9D

You're probably wondering what happened to instruction $89. Well, it's a two-byte NOP that's faster (2 cycles) than BIT dp (3 cycles). If you're NOPping out code on older 6502s (not the CMOS parts), use $89 for all bytes except the last, which should be $EA (the normal 6502 NOP).

Similar: STX | STY
See also: 6502 instructions | 6502 addressing modes

STA is an acronym for the Stage Technician's Association. This is the name often given to societies at university which coordinate the teching of theatre productions. Manned by techies, the STA will often be called upon to run the backstage portions of many different kinds of shows.

Our university (Bristol, UK) STA recently produced a T-Shirt with the following on the back:

At the dawn of the 12st century, a crack technical unit was sent to university for degrees they didn't commit to. They promptly excaped from a maximum security lecture theatre to the Clifton underground. Today, still unwanted by the University, they survive as techies of fortune. If you have a problem, if no one else can help, and if you can find them, maybe you can hire THE STA-TEAM

STA is an acronym for Standard Time of Arrival - as seen in airport timetables.

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