Need to concatenate a string, #1+#2+#3=#123. Help!

laser-vector · 2010-11-05 23:38

[EDIT] i changed the title of this thread just because i didnt feel starting a new one was necessary. original title was: "Need a way to take 4 numarical ASCII chars and convert to a real number" the new issue im having is that i need to take and array of bytes

eg. Byte Variable[2]
Variable[0] = 1
Variable[1] = 2
Variable[2] = 3

and concatenate them into one Long so that the long equals the actual number #123

[original thread]

lets say im using a terminal program and i enter 1234,

how could i convert %00110001_00110010_00110011_00110100 (or ascii 1234)
to the actual number %00000000_00000000_00000100_11010010 (or #1234)??

only way i can think is to make a lookup table.. is there any easier methods anyone knows about?

Thanks!!!

laser-vector · 2010-11-06 00:40

ok so i've got something going.. but still need a little help

so think of N.Byte[n] as an array..

N.byte[0] = 1
N.byte[1] = 2
N.byte[2] = 3
N.byte[3] = 4

but now im a little stumped, any ideas on how to take 1, 2, 3 and 4 and make them = 1234??

heres the code by the way:

PUB ASCIIToNum(bytecnt) | C, N
        C := 0
        data := 0         
        Repeat         
          RXbyte := Debug.RXcheck            
          If RXbyte => 0
            Case RXbyte
              N0[0] :
                N.byte[C] := N0[1]
              N1[0] :
                N.byte[C] := N1[1]
              N2[0] :
                N.byte[C] := N2[1]
              N3[0] :
                N.byte[C] := N3[1]
              N4[0] :
                N.byte[C] := N4[1]
              N5[0] :
                N.byte[C] := N5[1]
              N6[0] :
                N.byte[C] := N6[1]
              N7[0] :
                N.byte[C] := N7[1]
              N8[0] :
                N.byte[C] := N8[1]
              N9[0] :
                N.byte[C] := N9[1]
              $0D   :
                c := (bytecnt - 1)
             other :
               Debug.Str(String("Error, not a valid number character!!"))
               return
               
            if c => (bytecnt - 1)               
               ????????Dont know what to do here??????               
               return
                     
           C++      
DAT

      N0      byte  $30, $00
      N1      byte  $31, $01
      N2      byte  $32, $02
      N3      byte  $33, $03
      N4      byte  $34, $04
      N5      byte  $35, $05
      N6      byte  $36, $06
      N7      byte  $37, $07
      N8      byte  $38, $08
      N9      byte  $39, $09

kuroneko · 2010-11-06 00:52

What about this? The function takes a string (assuming ["0"-"9"] only and length within long range) and returns the numeric result.

PRI cnv(addr) | c

  repeat while c := byte[addr++]
    result := result * 10 + (c - "0")

laser-vector · 2010-11-06 01:23

Hey thanks for the reply! im having a little trouble with that example, maybe its just something im doing..

either way you did give me an idea for a better way to collect those ascii bytes and convert them to actual numbers.

VAR

        byte AsciiNumbers[9] 

PUB ASCIIToNum(DecimalCount) | C, N

        Repeat C from 0 to 9
          AsciiNumbers[c] := 0
        C := 0
        data := 0                   
        Repeat         
          RXbyte := Debug.RXcheck            
          If RXbyte => 0
            case RXbyte
              $30..$39 :
                AsciiNumbers[c] := RXbyte - $30
              $0D   :
                c := (DecimalCount - 1)
             other :
               Debug.Str(String("ERROR"))
               return                 
            if c => (DecimalCount - 1)
               repeat c from 0 to (DecimalCount - 1)           
                 Debug.str(num.tostr(AsciiNumbers[c], num#hex))                
               return                     
           C++

that is so much smaller and can read more ascii bytes thus making much larger numbers!

but im still stumped on how to make 1 + 2 = 12???????????

kuroneko · 2010-11-06 01:38

What about this then? The function reads characters from serial-in and aborts conversion for any non-numerical character.

CON
  _clkmode = XTAL1|PLL16X
  _xinfreq = 5_000_000
  
OBJ
  Debug: "FullDuplexSerial"

PUB null

  Debug.start(31, 30, %0000, 115200)
  waitcnt(clkfreq*5 + cnt)

  repeat
    Debug.dec(cnv)
    Debug.tx(13)
  
PUB cnv | RXbyte

  repeat               
    RXbyte := Debug.RX                       
    case RXbyte
      "0".."9":
        result := result * 10 + (RXbyte - "0")
      other:
        return

DAT

laser-vector · 2010-11-06 01:48

@ kuroneko

hey man thanks for the input, the code you posted looks oddly familiar to the code i just posted, proof that great minds do think alike!

lol
[edit] well it did look similar for a second there, but i guess you're currently editing it :P

its not the conversion of an ascii byte to a single digit number thats causing me grief, its more or less the process of concatenating those collected bytes into a number inside of a Long

eg. #1 + #2 + #3 + #4 = #1234 (not #10)

kuroneko · 2010-11-06 01:54

It's not rocket science!

The red line is executed 4 times for an input of "1234" + CR.

PUB cnv | RXbyte

  repeat               
    RXbyte := Debug.RX      ' blocking call                 
    case RXbyte
      "0".."9":
        [COLOR="Red"]result := result * 10 + (RXbyte - "0")[/COLOR]
      other:
        return

result starts with 0 and will now be 0 * 10 + 1 = 1
result = 1 * 10 + 2 = 12
result = 12 * 10 + 3 = 123
result = 123 * 10 + 4 = 1234
loop breaks (CR is not in [0..9]) and result is returned as 1234

the code you posted looks oddly familiar to the code i just posted

I just re-used it for convenience.

laser-vector · 2010-11-06 02:10

Ok i gotcha, yea i was really over complicating this! lol

i must have been looking at this from a totally different angle and didnt grasp the simplicity of your example untill i actually plugged it in and gave it a go.

guess thats what sleep deprivation, 5am, no coffee and a boss whos giving unreal deadlines will do to a fella..

Thank you!!

Need to concatenate a string, #1+#2+#3=#123. Help!

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