24 lines
777 B
Plaintext
24 lines
777 B
Plaintext
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.ifndef INCLUDE_UTILITY
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INCLUDE_UTILITY = 1
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.macpack longbranch ; jeq, jge...
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;********************************************************************************
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; @macro Update a byte in memory using a mask
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; @param orignal Address of the byte to update
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; @param new New value
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; @param mask Mask of the bits to affect by the new value
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; @details
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; xor new with original -> only bits that need to flip are 1
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; and result with mask -> only selected bits that need to flip stay 1
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; xor result with original -> flips selected bits
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;********************************************************************************
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.macro UT_update_with_mask original,new,mask
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lda #new
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eor original
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and #mask
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eor original
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sta original
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.endmacro
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.endif
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