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6502 Assembly Language Lab (Old Version)

1,007 bytes removed, 01:21, 16 September 2021
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5. Test the code by pressing the Assemble button, then the Run button. If the there are any errors assembling (compiling) the code, they will appear in the message area at the bottom of the page. Make sure the code is running correctly and that everyone in your group understands how it works.
 
6. Add this instruction after the <code>loop:</code> label and before the <code>sta ($40),y</code> instruction:
tya
 
7. What visual effect does this cause, and how many colours are on the screen? Why?
 
8. Add this instruction after the <code>tya</code>:
lsr
 
9. What visual effect does this cause, and how many colours are on the screen? Why?
 
10. Repeat the above tests with two, three, four, and five <code>lsr</code> instructions in a row. Describe and explain the effect in each case.
 
11. Repeat the tests using <code>asl</code> instructions instead of <code>lsr</code> instructions. Describe and explain the effect in each case.
 
12. Remove the <code>tya</code> and all <code>asl</code> and <code>lsr</code> instructions.
 
13. The original code includes one <code>iny</code> instruction. Test with one to five consecutive <code>iny</code> instructions. Describe and explain the effect in each case. '''Note:''' ensure that the Speed slider is on its lowest setting (left) for these experiments.
=== Writing Code, Part 1 ===

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