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49 lines
683 B
Markdown
49 lines
683 B
Markdown
---
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title: "6809"
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aliases:
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tags:
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- cosc204
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---
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# Routines
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All variables are global so there is no params or local vars.
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There are three way to "Branch" to a subroutine.
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- lbsr
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- bsr
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- jsr
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There are subtle differences but we will use bsr mostly
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```
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bsr myroutine:
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myroutine:
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rts
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```
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# Iteration
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Done using GOTOs
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```
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clra //A = 0
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more:
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cmpa #$06 //compare A to $06 (sets the equal flag in CC if true)
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beq done //if the equal flag is set, branch to done
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inca //increment a
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bra more //branch to more
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done:
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```
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other instructions set flags too
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# Input/Output
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# Hello World
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# Assembler
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