String to number conversion

[dj.lambert]

Hi All
i have a project where i use a pic to communicate with a power analyser.
the problem is all i can get from the analyser is a string, the string length is dependant on the measurements i request.but the returned format is for example "1.234567E1V 1.234567E-1A"

any ideas how to convert this to real usable numbers?

i have searched the forum but nothing similar seems to have been covered.

thanks in advance.

[be80be]

You may be able to look at this and work it out in PBP

It's from sowrdfish basic

Public Function StrToDec(pValue As String) As LongWord
   Dim Value As Byte
   Dim IsSigned As Boolean
   
   FTextAddress = @pValue
   Result = 0
   Value = FTextIn
   IsSigned = false
   If Value = Byte("-") Then
      IsSigned = true
      Value = FTextIn
   EndIf   
   While Value <> 0 
      Result = 10 * Result + (Value - 48)
      Value = FTextIn
   Wend
   If IsSigned Then
      Result = Not Result
      Inc(Result)
   EndIf   
End Function
{

[Jerson]

PBP does not support floats. So, converting those numbers will be difficult.

However, if like a challenge, this is a rough draft of how I would try my hand at it. This is not the best code that can be written for this though; just a pointer.

IntResult = 0
FractionResult = 0
Exponent = 0
Units = ""
WhichPart = 0                   ' 0 = Integer part, 1 = fractional part, 2 = exponent part
ExpFlag = 0                       ' set to 1 when reading the exponent
Pointer = points to start of number

while (character@Pointer != end of string)
    select case WhichPart
    case IntPart:              ' whichpart = 0
        IntResult = IntResult * 10
        select case character@pointer
        case "0" to "9":
               IntResult = IntResult + (character@pointer-'0')
        case "."
               WhichPart = 1         ' now on, gather fractional part
        end select
    case FractionalPart:      ' whichpart = 1
        FractionResult = FractionResult * 10
        select case character@pointer
        case "0" to "9":
               FractionResult = FractionResult + (character@pointer-'0')
        case "e" OR "E":
               WhichPart = 2         ' now on, gather Exponent
        end select
    case ExponentPart:              ' whichpart = 2
        Exponent = Exponent*10
        select case character@pointer
        case "0" to "9":
               Exponent = Exponent + (character@pointer-'0')
        case else
               Units = character@pointer
        end select
    end select

    ' move to the next character
    increment Pointer by 1
wend

This is purely 'pseudo code' and not PBP though it looks a bit alike. At the end of this routine, you should have 4 values - Integer result, Fractional Result, Exponent and Units either V or A. Now, you combine them as you deem fit and have your resulting answer

Regards

[BrianS]

Try this works great for me. Handles string to float conversions and can be connected to other microcontrollers. Also supports Picbasic Pro with examples.

http://www.micromegacorp.com/umfpu-v3.html

Bryan

[dj.lambert]

thanks for all the ideas.