Trevor Merritt
e29ac45c84
scroll left and right work in stdef and hidef adds octo test roms adds schip fonts to memory
56 lines
821 B
Plaintext
56 lines
821 B
Plaintext
###########################################
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#
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# A modular stack data structure using
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# a v0-based calling convention.
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# This approach reserves a dedicated
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# register for a stack pointer and as
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# a result is very simple and fast.
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# maximum stack size is 256 bytes.
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#
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###########################################
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:alias stack-ptr vd
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: stack 0 0 0 0 0 0 0 0
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: push
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i := stack
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i += stack-ptr
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save v0
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stack-ptr += 1
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;
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: pop
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stack-ptr += -1
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i := stack
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i += stack-ptr
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load v0
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;
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###########################################
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#
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# Usage Example:
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#
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###########################################
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: print
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# takes an arg in v0
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i := hex v0
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sprite va vb 5
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va += 6
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;
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: main
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va := 3
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vb := 3
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v0 := 5 push
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v0 := 3 push
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v0 := 1 push
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pop print
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v0 := 9 push
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pop print
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pop print
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pop print
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# should print '1935'
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