43 lines
648 B
ArmAsm
43 lines
648 B
ArmAsm
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.include "t-macros.i"
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start
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# Establish `interrupt..einterrupt' at the NMI interrupt address
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load r1 interrupt
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load r2 einterrupt
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load r3 INT_NMI
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copy: ld.b 0[r1], r4
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st.b r4, 0[r3]
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add 1, r1
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add 1, r3
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cmp r1, r2
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bge copy
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# Keep looping until r1 becomes non zero - a tick
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mov 0, r1
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mov 0, r2
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loop: cmp 0, r1
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be loop
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# Print the message indicating that a tick was encountered
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mov 4, r6
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mov 1, r7 # FID
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load r8 tick # string
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load r9 etick-tick # size
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trap 31
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mov 0, r1
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add 1, r2
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cmp 10, r2
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blt loop
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exit0
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interrupt:
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mov 1, r1
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reti
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einterrupt:
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.data
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tick: .ascii "Tick\n"
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etick:
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