Send string through serial port

mytrax

Hi,

I burned my brain since two days looking for a solution !
I got some trouble with RS232 communication. I wrote a VB.net program in order to send to the propeller the coordinates of a joystick connected to my PC . I can receive those data but I can't differentiate them. Take a look :

Part of my VB.net Prog :

I send those informations to my propeller :

RS232.WriteLine(state.Y)
RS232.WriteLine(state.X)
RS232.WriteLine(state.GetPointOfView(0))
RS232.WriteLine(state.GetSlider(0))
RS232.WriteLine(state.Rz)

And I receive them with the "Full-Duplex_COMEngine" object like that :

serial.readString(@data, 512)

The problem is that I can't differentiate all the incoming datas. I would like to put state.Y , state.X ... in differents VAR. Or maybe in an array.

I tried that :

repeat until index == 4
char := serial.readString(@data, 512)
str[index] := char
index++

but it doen't works

Could you help me please ? Sorry but I'am a newbie :-D

Duane Degn

What does the data look like coming out of the PC? How is it formatted?

It helps if you use code tags when posting code. Here's a link to learn how.

turbosupra

You need to make sure the vb.net is sending at the same protocol values that the receiving object on the propeller is expecting, say it is fullduplexserial or the parallax serial terminal, 8N1, 8 bits, no parity, 1 stop bit.

I do this with code like this, if you need more specific help, we'll need more specifics and specific code

l_myReceivedByte := pst.RxCheck
       
      if l_myReceivedByte <> -1
        b_waitingToBeParsed[b_byteMoveIndex++] := l_myReceivedByte
       
        ' pst.str(@b_waitingToBeParsed)
        ' pst.str(string(pst#NL))
       
        if l_myReceivedByte == 13
          DelimiterFinder(@b_waitingToBeParsed)
          ByteFill(@b_waitingToBeParsed, 0, strsize(@b_waitingToBeParsed))
          b_byteMoveIndex := 0

PUB DelimiterFinder(RxStringAddr) : idx | localCount, localIndex, pstDelimiterFinder                                            

  ' Initialize variables here
  localIndex := 0
  pstDelimiterFinder := 0

  repeat
    ifnot localCount := byte[RxStringAddr][idx++]                ' ifnot c, itterate to the next byte in byte[RxStringAddr] ?
    
      printAt( 1,12, String("No delimiter, aborted"))
      return -1

    charAt(1+idx,13,localCount)
    ' pst.dec(localCount)
    ' pst.str(string(pst#NL))  
  until localCount == b_delimiter'localCount == "="
 
  bytemove(@b_prefix, RxStringAddr, --idx)              ' idx points to the character after the delimiter, copy prefix
  b_prefix[idx] := 0                                    ' add terminator  
  RxStringAddr += idx + 1                               ' advance pointer, skip delimiter (+1)                                                 
  bytemove(@b_suffix, RxStringAddr, strsize(RxStringAddr) +1)                   ' copy tail including the existing terminator (+1)
  variableUpdator(@b_prefix, @b_suffix)

mytrax

Hi,

Thanks for your answer, but I'a code, I'am a real newbie !
For more informations ; in fact I would send that through my pc : "122|999|647|455" and catch all numbers between "|" and put them in differents variables.

I tried to wrote my code ; take a look :

PUB StrParse(strAddr, start, count)


count <#= constant(STR_MAX_LENGTH - 1)
bytemove(@ostr, strAddr + start, count) ' just move the selected section


ostr[count] := 0 ' terminate string
RETURN @ostr


Pub Parse(Mystr) | BarPos, FindStr, nextstr, count, numletter, field, letter


count := 0
field := 0
numletter := 0
BYTEFILL(@parsed, 0, 40)
BYTEFILL(@cmdfield, 0, 40)


repeat strsize(Mystr)


letter := StrParse(Mystr,numletter,1)


if parsed[count] == "|"
cmdfield[field]:= @parsed
field++
count := 0
BYTEFILL(@parsed, 0, 40)


else
parsed[count] := letter
count++
serial.str(parsed[count])
serial.newline

numletter++

But it doen't worl , I think I'am near the solution ! Help me please ^^ !

turbosupra

Sorry Mytrax,

I just saw your reply. Try the example I've attached and see if you can adapt it to what you'd like to do.

If you type "bob=100" you'll see it parse through the data and give the values before the equals sign and after the equals sign.

Let me know how this works for you.

Duane Degn

mytrax wrote: »

in fact I would send that through my pc : "122|999|647|455" and catch all numbers between "|" and put them in differents variables.

It would help if you took another look at the code tags link I posted earlier. Using a quote block doesn't keep the indentation that is so important in Spin.

I see you want to use "|" as a delimiter but you're sending values that you want stored in certain variables right? What indicator is there to indicate a new message? What are the end of messae charaters?

It's common to use a carriage return to indicate an end of message. It would also help if you had some sort of beginning of message indicator.

Is the data "122|999 etc" sent as ASCII characters? Where "122" is three bytes?

You mentioned you want the data assigned to various variables. In your example where you're sending four numbers, do you want to keep reusing the same four variables (such as (I'm just making these up) "xAxis", "yAxis", "zAxis" and "buttonValue")?