Check-sum using xor ^

Comments

• L_Gaminde Posts: 29

  2013-07-07 11:02 edited 2013-07-07 11:02

  Well this is what I came up with!
  ' {$STAMP BS2}
  ' {$PBASIC 2.5}
  a VAR Word
  b VAR Word
  z VAR Word
  
  start:
  FOR a = 48 TO 57
  FOR b = 48 TO 57
  z = 59 ^a ^b ^78
  DEBUG a,b," ",a,b,"N",HEX z,CR
  PAUSE 500
  NEXT
  
  FOR b = 65 TO 70
  z = 59 ^48 ^b ^78
  DEBUG a,b," ",a,b,"N",HEX z, CR
  PAUSE 500
  NEXT
  NEXT
  
  FOR a = 65 TO 70
  FOR b = 48 TO 57
  z = 59 ^a ^b ^78
  DEBUG a,b," ",a,b,"N",HEX z,CR
  PAUSE 500
  NEXT
  
  FOR b = 65 TO 70
  z = 59 ^48 ^b ^78
  DEBUG a,b," ",a,b,"N",HEX z, CR
  PAUSE 500
  NEXT
  NEXT
  
  
  END
• Tracy Allen Posts: 6,667

  2013-07-07 11:20 edited 2013-07-07 11:20

  Larry, not sure if this does what you want. It runs the a and b variables from 48 to 63, but translates the values from 58 to 63 up to "A" to "F".
  

  [SIZE=1][FONT=courier new]a VAR BYTE
  x VAR BYTE
  b VAR BYTE
  y VAR BYTE
  z VAR WORD
  FOR a=48 TO 63
    IF a>57 THEN x=a+7
    FOR b=48 TO 63
      IF b>57 THEN y=b+7
      z = 59 ^ x ^ y ^ 78
      DEBUG x,y," ",x,y,"N",HEX z,CR
      PAUSE 500
    NEXT
  NEXT
  [/FONT][/SIZE]
  

  
  The bitwise xor operation is commutative, so I think you can replace the 59^78 with one ^117.
• L_Gaminde Posts: 29

  2013-07-07 11:39 edited 2013-07-07 11:39

  Yes i think this is what i wanted, i changed the x and y to a and b so it would print out from 00 to FF
  thanks Tracy I think this is the first thing you posted for me that I did not have to look at for a few hours to understand. after 10 years I'm still trying to figure out your Julian stuff.
  
  SO is there a way to print out the Debug list?
  
  ' {$STAMP BS2}
  ' {$PBASIC 2.5}
  a VAR Byte
  x VAR Byte
  b VAR Byte
  y VAR Byte
  z VAR Word
  FOR a = 48 TO 63
  IF a > 57 THEN a = a + 7
  FOR b = 48 TO 63
  IF b > 57 THEN b = b + 7
  z = 59 ^ a ^ b ^ 78
  DEBUG a,b," ",a,b,"N",HEX2 z,CR
  PAUSE 100
  NEXT
  NEXT
• Tracy Allen Posts: 6,667

  2013-07-07 12:30 edited 2013-07-07 12:30

  Hmmm. I'd think that adding 7 to the actual loop variable would mess up the loop execution. That's why I threw in x and y.
  
  The value of z is the only one being printed out as 00 to FF.
  
  Print out the debug list--Capture the list using a terminal program, Putty, CoolTerm, Hyperterminal etc. Then print the text file.
  
  (Ah, Julian time is quite a numbers game!)
• L_Gaminde Posts: 29

  2013-07-07 12:39 edited 2013-07-07 12:39

  yea ok I lied! it is going to take some time
  yours starts at AA and goes to FF but skips the lower set 00 to 9F because of the X-Y in the debug statement so I need to implement you thinking into something a little different.