all repos — xyw @ 72c00afbbe49afa44632bb40550d12161656b892

A minimal virtual machine and assembler for terminals.

examples/lib/upcase.xyw

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; Convert a string to uppercase 
; a16 ->
.label upcase
  ; store index
  POPxw
  .label upcase.loop
    LDBxw $00 EQU upcase.end JCNw
    ; check if a lowercase letter
    LDBxw $60 GTH
    LDBxw $7B LTH
    AND upcase.change JCNw
    ; continue
    INCxw upcase.loop JMPw
    .label upcase.change
      ; convert to uppercase  
      LDBxw $20 SUB STBxw
      ; continue 
      INCxw upcase.loop JMPw
    .label upcase.end
      RTS