Capital after Vowel, ASM version

2022-12-19.asm

START:  LDY #00     ; start loop at 0
LOOP:   LDA $0800,Y ; load Y-th character
        BEQ _END    ; stop loop if NULL found
TRY_A:  CMP #61     ; compare to 'a'
        BNE _TRY_E
        JSR _VOWEL  ; found a vowel
        INY         ; next character
        JMP _LOOP
TRY_E:  CMP #65     ; compare to 'e'
        BNE _TRY_I
        JSR _VOWEL
        INY
        JMP _LOOP
TRY_I:  CMP #69     ; compare to 'i'
        BNE _TRY_O
        JSR _VOWEL
        INY
        JMP _LOOP
TRY_O:  CMP #70     ; compare to 'o'
        BNE _TRY_U
        JSR _VOWEL
        INY
        JMP _LOOP
TRY_U:  CMP #75     ; compare to 'u'
        BNE _SKIP
        JSR _VOWEL
        INY
        JMP _LOOP
SKIP:   CMP #20     ; compare to ' '
        BNE _CONST
        INY
        JMP _LOOP
CONST:  CPX #00     ; compare Y to False
        BEQ _PRINT  ; skip over...
        SBC #20     ; reduce A by 32
        JSR _RESET  ; reset X
PRINT:  JSR $FFD2   ; 6502 print routine location
        INY
        JMP _LOOP
END:    BRK
VOWEL:  LDX #01     ; set X to True
        RTS         ; return
RESET:  LDX #00     ; set X to False
        RTS         ; return