[stella] ASM comparison question

Subject: [stella] ASM comparison question
From: "Dennis Debro" <dennis@xxxxxxxxxxxxxxx>
Date: Wed, 25 May 2005 10:05:45 -0400
Hi there,

I seem to be missing something. I'm trying to take a random number and
make it stay between 9 and 149. The code I have is...

   jsr RandomByte            ; get a random number
   cmp #9                    ; compare with lower limit
   bcs .checkUpperRange      ; check upper limit if >= lower
   adc #9                    ; here value < lower so add lower limit
   cmp #150                  ; compare with upper limit + 1
   bcc .storeBetweenValue    ; if < upper then in range
   sbc #149                  ; subtract upper limit
   bcs .checkLowerRange      ; shouldn't cross 0 so unconditional branch
   sta betweenValue

I've looked at this for so long that maybe I can't see the forest for the
trees. Sometimes I'm getting a number out of the range. Should this work?

Take care,

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