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JoshTGreenwood/gist:27e81638428225e2bc0f

Created June 20, 2014 17:42
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  1. JoshTGreenwood created this gist Jun 20, 2014.
    52 changes: 52 additions & 0 deletions gistfile1.txt
    View file
    Original file line number Diff line number Diff line change
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    /*
    * midterm.asm
    *
    * Created: 6/20/2014 11:41:46 AM
    * Author: Josh
    */

    .org 0x0
    ldi r29,0x00
    ldi r30,0x10
    ldi r31,0xFF

    start:
    // sets PORTE data direction to read
    sts PORTE_DIR, r29

    // loads the contents of PORTE to r16
    lds r16, PORTE_IN

    // sets X pointer register to 0
    clr XL
    clr XH

    search:
    // load to r17 from X pointer register
    ld r17,X+

    // check to make sure it isn't comparing r17 with r16
    cpi r17, 0x10 // 0x10 is the location of r16

    breq search

    // compare r16 and r17
    cp r16,r17

    // if equal, light led
    breq lightLED

    // if at end of memory, restart
    rjmp start

    // go back to search
    rjmp search

    lightLED:
    // sets PORTF data direction to write
    sts PORTF_DIR, r30

    // loads the contents of PORTE to r16
    sts PORTF_OUT, r31
    // infinite loop
    rjmp lightLED