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Best way to mirror a byte?

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Hey guys, I was looking for a quick/cheap on ROM way to mirror the bit order in a byte.  The input is a byte in the order 7 6 5 4 3 2 1 0, with the output 0 1 2 3 4 5 6 7.  The intention is to use this function on playfield graphics to get over the hardware mirroring of PF0 and PF2.  This is what I came up with:



    ldy #0
    sty temp

    ldy #$88
    sty temp2    

    jsr ROR_W_Carry
    and temp2
    ora temp
    sta temp
    jsr ROR_W_Carry    
    lsr temp2
    bcc Mirror_Loop
    lda temp


    and #$01
    beq Mirror_D0_Not_Set




The value to be mirrored is passed to the subroutine in the accumulator, and returned mirrored in accumulator and temp.  You just need to jsr Mirror_Byte to get the result.  I don't really like that it uses another jsr to do the RORing, or the amount of time this all takes.. Im sure the loop can be altered to eliminate one instance of jsr ROR_W_Carry at a minimum.  Anyone have a better way?

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