Kleiner Parser (Befehlszeile) für AVR uC

Hi all,

Hier zu eurer Verfügung ein Progrämmchen, mit dem ein AVR Befehle wie ein Modem "at irgendwas" annehmen kann. Die Eingabezeile wird in bis zu acht Worte zu 16 Zeichen zerlegt, die man dann untersuchen und darauf Unterprogramme starten kann.

Ich brauchte das, weil ich mehrere Controller über Bluetooth via meinem Android-Telefon erreichen wollte.

Gruss
snafu

Code:

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'receiving input from serial interface, test for leading "at" string and
'interprete various commands to be executed in subroutines



$crystal = 20000000
$regfile = "m168def.dat"

$baud = 38400

Config Portc.4 = Output
Weiss_0 Alias Portc.4

Config Portc.5 = Output
Weiss_1 Alias Portc.5

Config Portd = Output
Config Lcdbus = 4
Config Lcd = 20 * 2                                        'configure lcd screen
Config Lcdpin = Pin , Db4 = Portd.4 , Db5 = Portd.5 , Db6 = Portd.6 , Db7 = Portd.7 , E = Portd.3 , Rs = Portd.2
Rem with the config lcdpin statement you can override the compiler settings

'all neccessary for interrupt input of serial chars
Dim Ser_rx_char As String * 1
Dim Ser_rx_char_byte As Byte
Dim Serialinput As String * 100                            'int routine is collecting input string in this variable
Dim New_input_string As String * 100                        'if complete string received it will be saved here
Dim Parse_string As String * 100                            'parser gets this string
Dim New_input_string_received As Bit
Dim Input_zaehl As Byte
Dim String_len As Byte

'variablen für den parser
Dim Parser_string_len As Byte
Dim Parser_split_pointer As Byte
Dim Parse_wd(8) As String * 16
Dim Parse_wd_counter As Byte

'hardware UART is used
Config Serialin = Buffered , Size = 10                      'PD0 = TXO, PD1 = RXI
                                                            '10 Byte input buffer
Enable Interrupts                                          'neccessary because uart fires interrupt if new char received


'-------------- INIT -----------------------------------------------------------

Cls
Upperline
'---"01234567890123456789"
Lcd "PARSER"
Lowerline
Lcd "0.32"
Cursor Off Noblink

Serialinput = ""                                            'Inputpuffer reset
New_input_string = ""                                    'input string reset reset
New_input_string_received = 0                        'flag reset
Print "--- RESET ---"


'-------------- MAIN -----------------------------------------------------------
Do
'-------------- fetch waiting chars
  If Ischarwaiting() = 1 Then                              'poll buffer of uart routine
      Gosub Serial_zeichen_abholen
  End If

'-------------- test for new input string
  If New_input_string_received = 1 Then            'complete string was received
      New_input_string_received = 0                  'flag reset
      Parse_string = New_input_string                    'prepare string for parser
      Print
      Gosub Parse_input_string                              'analyze words in received string
  End If
Loop

'-------------- end MAIN -------------------------------------------------------



'-------------- subroutines ----------------------------------------------------

Parse_input_string:
'-------------- parse input string
  For Parse_wd_counter = 1 To 8

      'strip leading blanks
      While Left(parse_string , 1) = " "
        Parser_string_len = Len(parse_string)
        Parser_string_len = Parser_string_len - 1
        Parse_string = Right(parse_string , Parser_string_len)
      Wend

      'find first blank char
      Parser_split_pointer = Instr(parse_string , " ")      'look for first blank character

      If Parser_split_pointer > 0 Then                  '= 0 if no blank found
        Parser_split_pointer = Parser_split_pointer - 1
      End If

      'isolate first parse word
      If Parser_split_pointer > 16 Then                  'avoid to set Parse_wd(n) with strings longer than 16 chars
        Parser_split_pointer = 16
      End If
      Parse_wd(parse_wd_counter) = Mid(parse_string , 1 , Parser_split_pointer)

      'reduce parse string to remaining chars which are still due to parse
      If Parser_split_pointer > 0 Then                  '
        Parser_split_pointer = Parser_split_pointer + 1
        Parser_string_len = Len(parse_string)
        Parser_string_len = Parser_string_len - Parser_split_pointer
        Parse_string = Right(parse_string , Parser_string_len)
      Else                                              'last command word in parse string found
        Parse_string = ""
      End If
      'Print "[" ; Parse_wd(parse_wd_counter) ; "]";

  Next

'-------------- interprete commands with arguments
  Select Case Parse_wd(1)
      Case "at" : Gosub Attention
      Case Else
        Print "missing at string, received: [" ; Parse_wd(1) ; "]"
        Print "send [at command argument]"
  End Select
Return

'-------------- commands
Attention:

  Select Case Parse_wd(2)
      Case "led0" : Gosub Led0
      Case "led1" : Gosub Led1
      Case Else
        Print "missing or wrong command, received: [" ; Parse_wd(2) ; "]"
        Print "send [led0 | led1]"
  End Select
Return


Led0:
  Select Case Parse_wd(3)
      Case "on"
        Weiss_0 = 1
        Print "ok"
      Case "off"
        Weiss_0 = 0
        Print "ok"
      Case Else
        Print "missing or wrong argument, received: [" ; Parse_wd(3) ; "]"
        Print "send [on | off]"
  End Select
Return

Led1:
  Select Case Parse_wd(3)
      Case "on"
        Weiss_1 = 1
        print "ok"
      Case "off"
        Weiss_1 = 0
        Print "ok"
      Case Else : Print "missing or wrong argument, received: [" ; Parse_wd(3) ; "]"
  End Select
Return






'-------------- receive serial characters --------------------------------------
' collect received chars and assemble them to input string

Serial_zeichen_abholen:
If Ischarwaiting() = 1 Then
  Ser_rx_char = Inkey()
  Ser_rx_char_byte = Asc(ser_rx_char)
  String_len = Len(serialinput)

  Select Case Ser_rx_char_byte
      Case 13                                              'return chra was recognized
        New_input_string = Serialinput                  'copy string for main routine
        New_input_string_received = 1              'set flag that new string is ready
        Serialinput = ""                                  'reset all for new string
        Ser_rx_char = ""
      Case 127                                              'backspace - char
        If String_len > 0 Then
            Print Chr(8) ; " " ; Chr(8);                    'android recognizes no chr(127), therefore i use backspace, writing blank, backspace again
            String_len = String_len - 1
            If String_len = 0 Then                          'because "left" returns even with (string,0) one char
              Serialinput = ""
            Else
              Serialinput = Left(serialinput , String_len)
            End If
        End If
      Case Is < 32                                          'drop all ather control chars
        Ser_rx_char = ""
      Case Is > 127
        Ser_rx_char = ""
      Case Else                                            'valid input char
        If String_len < 100 Then                          'room left in input string?
            Serialinput = Serialinput + Ser_rx_char        'append received char
            Print Ser_rx_char ;                            'and echo via serial
        Else                                              'abort if 99 chars without enter received
            New_input_string = Serialinput              'then string will be closed without enter
            Serialinput = ""
            New_input_string_received = 1
            Ser_rx_char = ""
        End If
  End Select

End If
Return

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