programming help

Dirty Howi · 2013-11-22 13:09

I am trying to send a message to my basic stamp using COM6 (its the port that's id'd by the software). I am sending a string of 4 characters, based on that i want a simple select to turn on one of three lights (to wit)

serStr VAR Byte(10)
serStr(9)=0
SERIN 1, 16468, [STR serStr\9]
SELECT serStr
CASE "ormd"
HIGH 15
PAUSE 2000
LOW 15
ENDSELECT

i can see the lights blink on the basic stamp proto module, so i know i'm sending something, unfortunately i cant run both at the same time (the BS2 debugger and my code)

        private void btnORMD_Click(object sender, EventArgs e)
        {
            var c = new communications();
            c.SendMessage("ormd");
        }

and to open a com port

  public  class communications
  {
      private SerialPort sp = new SerialPort();
      public communications()
      {
          sp.PortName = "com6";
          sp.BaudRate = 9600;
          sp.Parity = Parity.None;
          sp.DataBits = 8;
          sp.StopBits = StopBits.One;
          sp.Handshake = Handshake.None;

      }

      public void SendMessage(string message)
      {
          sp.Open();
          sp.WriteLine(message);
      }

  }
}

any help for the dumb puter programmer would be appreciated

Beau Schwabe · 2013-11-22 13:51

The most common problem is a signal inversion issue... if you see light's then obviously you are wiggling something, but it may appear dead or you will see garbage characters in the monitor terminal. can you scope the data line? Between byte sends is the voltage level predominately high (TRUE) or is it low (INVERTED)?

Dirty Howi · 2013-11-22 14:00

i'm sending this via a windows app i wrote (quick and dirty), if i open the program in the debugger, i cant talk to the port since the debugger has a hold of it, if i dont run the debugger, my software works (flashes lights next to the microcontroller) but the led wired to p15 does not come on. I'm using the built in USB cable to communicate via COM6. I dont have a scope or meter available to check the levels (i'll have to dig around in the tool box LOL). Not had a scope available in oh 30 years or so.

Anyway to send the command via the debugger (i'm still reading the books)

Beau Schwabe · 2013-11-22 14:27

Just for kicks, try "84" instead of "16468" on the Basic Stamp.... 84 - is 9600 baud non-inverted 16468 - is 9600 baud inverted ... both are 8 bit no-parity

Beau Schwabe · 2013-11-22 14:49

Also... the expression for the select case is a variable, constant or an expression. Pointing to a string might not be valid. Depending on exactly what you want to accomplish, the WAIT condition might be more suitable.

Dirty Howi · 2013-11-22 14:58

i'll give that a shot (the 84) when i get it all hooked back up, took it apart to bring it home from the office

off next week. will post results.

Dirty Howi · 2013-11-25 18:13

no joy...hmm....all i want to send is one of three values, ormd, ormdw, haz. One for each of the three lights. Its just a proof of concept to show the company owner...this should not be this hard.

anyone have a example of talking to a basic stamp via .NET (VB or C# dont matter to me, i read/write both and can translate between them)

Unsoundcode · 2013-11-26 08:22

Hi, this line

SERIN 1, 84, [STR serStr\9]

receives an array of nine bytes. If the array is less than nine or if the length of the array is going to vary then you would need to transmit an end of line character or your Stamp program is just going to hang there.

For example attaching a carriage return as the end of line would be handled as follows by the Stamp

SERIN 1, 84, [STR serStr\9\CR]

this would inform the Stamp that a complete string had been received and we can move on.

Secondly serStr is an array of byte variables and the values or string that it contains must be extracted one byte at a time using the index of the element eg: serStr(0) ,serStr(1)......... so Select Case will not work on the string as a whole only the individual elements.

As proof of concept try your program with just a one byte variable to begin with.

The following link is a 2007 post that has a few useful references in it although I now know there is plenty of room for improvement.

http://forums.parallax.com/showthread.php/96973-VB-Express-to-Stamp-Template

Jeff T.

Dirty Howi · 2013-11-26 14:18

i'll get my sign out now lol. i'll build an enum to pass one byte values to test it. i'll also look at the links when i get home. after im done feeling like an embicile

thanks

Unsoundcode · 2013-11-26 15:04

I certainly don't believe you are an imbecile although I know too well the feeling <g>

Your project is the kind I get into and the kind I have struggled with in the past.

What you are attempting is well within the capabilities of the Stamp and you have probably witnessed already the willingness to help by the members of this forum.

So just keep posting your questions and you are guaranteed a helpful response.

Jeff T.

Dirty Howi · 2013-11-28 07:14

i've an odd feeling i know this, but if i send a "message" via the C# program as a string it has to go as "1" which on the other end in computerdom is interpreted as 1 not "1"; is the stamp seeing "1" and not 1? if that's the case then am i better off sending it as an int?

edit: never mind the int, the serial port class writeline method will only accept a string

Unsoundcode · 2013-11-28 08:18

Hi, the three main options are

1) write a binary array of one or more values

Dim mybyte() As Byte = Nothing
        mybyte(0) = 1
        SerialPort1.Write(mybyte, 0, 1)
'Stamp receives 1

2) write a string of characters as ASCII character codes with a NewLine character appended. The default newline character has a value of decimal 10 but can be modified with the serial port method.

Dim terminated_string As String = "1"
        SerialPort1.WriteLine(terminated_string)
'Stamp receives "1" and then 10

3) write a string of characters as ASCII character codes without the NewLine appended.

Dim non_terminated_string As String = "1"
        SerialPort1.Write(non_terminated_string)
'Stamp receives "1"

When VB transmits ASCII characters, for example "1" is transmitted as the character code value of 49, then the Stamp must be set up to format the incoming data from a binary value to a string.

1) this accepts a transmitted value of "1" and stores 49 into the variable myvar.

SERIN port,baud,[myvar]

2) this accepts a transmitted value of "1" and stores 1 into the variable myvar.

[code]SERIN port,baud,[DEC myvar]

Formatters such as DEC and HEX take ASCII string character codes and convert them into their respective values at the Stamp.

Jeff T.

Dirty Howi · 2013-12-08 11:47

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Dim terminated_string As String = "1"
        SerialPort1.Open()
        SerialPort1.WriteLine(terminated_string)
        SerialPort1.Close()

    End Sub

what is in the button (i even moved over to VB since that's what your using)
program in the stamp itself

' {$STAMP BS2}
' {$PBASIC 2.5}
DEBUG "Program Running"

serStr VAR Byte

SERIN 1,82, [STR serStr \1]

  HIGH 15
  PAUSE 2000
  LOW 15

very simple wait for ANYTHING to come across, and light up the light...still no joy

and its snowing in iowa, and i have nothing else to do today cept play with this so...

Dirty Howi · 2013-12-08 12:27

ok, its official i'm an idiot.

when dealing with something new it pays to RTFM

SERIN 16, 84 [DEC strStr] works...it helps if you set the rpin portion of the command to the right dad gum pin LOL.

Chris Savage · 2013-12-09 09:59

Glad to see you figured it out and got it working. :thumb:

programming help

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