Private Sub Form_Unload(Cancel As Integer)
If MSComm1.PortOpen = True Then MSComm1.PortOpen = False
' This code assumes that you have a Form called SMS
' with the following on it:
' 1 x Microsoft COM Control V6.0
'
' DISCLAIMER
' This code and the information in it has been provided at no charge, for
' non commercial use and the author disclaims all liability of any kind
' relating to any use made of it
End Sub

Private Sub PDUEncoder_Click()
PDU.Show
' For details on the Nokia FBUS format, jump on the web and check out
' sites such as GNOKIA. There are also other sites which talk about
' the electronics needed to interface a PC or microcontroller to
' a Nokia phone that has an FBUS interface
'
' This code assumes that you have a Form called SMS
' with the following on it:
' 1 x Command Button (which is set to run this code when it is clicked)
'
' DISCLAIMER
' This code and the information in it has been provided at no charge, for
' non commercial use and the author disclaims all liability of any kind
' relating to any use made of it
End Sub

Private Sub SendSMS_Click()
' declare variables
Dim msg As String
Dim RdStr As String
Dim SndStr As String
Dim i
Dim FL As Integer

' clear the send and receive text boxes
Sent_String.Text = "": Rcvd_String = ""
SMS.Refresh

' if the COM port is closed, then open it
If MSComm1.PortOpen = False Then MSComm1.PortOpen = True

' ask for the message and get the PDU version
msg = InputBox("Message")
msg_pdu = Text_To_PDU(msg)

' get the SMSC phone number
' and convert it to FBUS format
Input_Phone = InputBox("SMSC Phone Number", , "+61411990010")
GoSub Convert_Phone_Number
SMSC_Number = Phone_Number

' get the SMS destination phone number
' and convert it to FBUS format
Input_Phone = InputBox("SMS Destination Phone Number", , "0431867231")
test_flag = True
GoSub Convert_Phone_Number

' set frame parameters
Frame_ID = Right$("0" & (CStr(Hex(&H1E))), 2)
DestDev = Right$("0" & (CStr(Hex(&H0))), 2)
SrcDev = Right$("0" & (CStr(Hex(&HC))), 2)
MsgType = Right$("0" & (CStr(Hex(&H2))), 2)
SMS_Frame_Hdr = Right$("0" & (CStr(Hex(&H0))), 2) & Right$("0" & (CStr(Hex(&H1))), 2) & Right$("0" & (CStr(Hex(&H0))), 2) & Right$("0" & (CStr(Hex(&H1))), 2) & Right$("0" & (CStr(Hex(&H2))), 2) & Right$("0" & (CStr(Hex(&H0))), 2)
SMSC_Details = SMSC_Number
Msg_Length_For_Calc = (Len(msg_pdu) / 2)
Msg_Text_Length = Right$("0" & CStr(Hex(Len(msg))), 2)
TPDU = Right$("0" & (CStr(Hex(&H15))), 2) & Right$("0" & (CStr(Hex(&H0))), 2) & Right$("0" & (CStr(Hex(&H0))), 2) & Right$("0" & (CStr(Hex(&H0))), 2)
vp = Right$("0" & (CStr(Hex(&HA7))), 2) & Right$("0" & (CStr(Hex(&H0))), 2) & Right$("0" & (CStr(Hex(&H0))), 2) & Right$("0" & (CStr(Hex(&H0))), 2) & Right$("0" & (CStr(Hex(&H0))), 2) & Right$("0" & (CStr(Hex(&H0))), 2) & Right$("0" & (CStr(Hex(&H0))), 2)
Frames_To_Go = Right$("0" & (CStr(Hex(&H1))), 2)
Seq_No = Right$("0" & (CStr(Hex(&H43))), 2)
Frame = Frame_ID & DestDev & SrcDev & MsgType & "00" & SMS_Frame_Hdr & SMSC_Details & TPDU & Msg_Text_Length & Phone_Number & vp & msg_pdu & Frames_To_Go & Seq_No

' Set Frame Length values
FL = (Len(SMS_Frame_Hdr) / 2) + (Len(SMSC_Details) / 2) + (Len(TPDU) / 2) + (Len(Msg_Text_Length) / 2) + (Len(Phone_Number) / 2) + (Len(vp) / 2) + (Len(msg_pdu) / 2) + (Len(Frames_To_Go) / 2) + (Len(Seq_No) / 2)
Frame_Length = FL

' check whether pad byte is necessary and add one
' if it is
Pad_Byte = ""
If FL Mod 2 <> 0 Then
' Frame is an odd length so add Pad Byte
Pad_Byte = Right$("0" & (CStr(Hex(&H0))), 2)
End If

' create frame
Buf_Frame = Frame
Frame = Left$(Buf_Frame, 10) & Right$("0" & CStr(Hex(Frame_Length)), 2) & Mid$(Buf_Frame, 11, Len(Buf_Frame) - 10)
Frame = Frame & Pad_Byte

' calculate checksums and add them to the frame
' there are two checksums for FBUS. The first
' is an exclusive or (XOR) of the characters in every
' odd position in the frame and the second is an
' exclusive or (XOR) of the characters in every even
' position in the frame (eg if a frame was
' 1E 0C 00 7F 00 02 02 03, the odd checksum value would
' be: 1E XOR 00 XOR 00 XOR 02 which results in a value
' of 1C and the even checksum byte would be:
' 0C XOR 7F XOR 02 XOR 03 which results in a value of 72
' note all values shown above are in hex
process_chr = ""
first_odd = True
first_even = True
char_pos = 0
For i = 1 To Len(Frame)
process_chr = process_chr & Mid$(Frame, i, 1)
If Len(process_chr) = 2 Then
Process_Value = CSng("&H" & process_chr)
char_pos = char_pos + 1
If char_pos Mod 2 <> 0 Then
' odd position
If first_odd = True Then
Odd_ChkSum = Process_Value
first_odd = False
Else
Odd_ChkSum = Odd_ChkSum Xor Process_Value
End If
Else
' even position
If first_even = True Then
Even_ChkSum = Process_Value
first_even = False
Else
Even_ChkSum = Even_ChkSum Xor Process_Value
End If
End If
process_chr = ""
End If
Next i
Odd_ChkSum = Hex(Odd_ChkSum)
Even_ChkSum = Hex(Even_ChkSum)
Frame = Frame & Right("0" & (CStr(Hex(CStr("&H" & Odd_ChkSum)))), 2) & Right("0" & (CStr(Hex("&H" & CStr(Even_ChkSum)))), 2)

' create a display friendly version of the frame to be sent
' so that we can display it
For i = 1 To Len(Frame)
Out_Chr = Out_Chr & Mid$(Frame, i, 1)
If Len(Out_Chr) = 2 Then
Output_Frame = Output_Frame & Out_Chr & " "
Out_Chr = ""
End If
Next i

' create sms command to go to phone
process_chr = ""
Send_String = ""
For i = 1 To Len(Frame)
process_chr = process_chr & Mid$(Frame, i, 1)
If Len(process_chr) = 2 Then
Send_String = Send_String & Chr$(CSng("&H" & process_chr))
process_chr = ""
End If
Next i

' display what we are about to send
For i = 1 To 127: Sent_String.Text = Sent_String.Text & "55 ": Next i
Sent_String.Text = Sent_String.Text & "55" & Chr$(13) & Chr$(10)
Sent_String.Text = Sent_String.Text & Chr(13) & Chr(10) & Output_Frame

' refresh the form to ensure that the values are displayed
SMS.Refresh

' send 128 'U's' (0x55) (55D) to start an FBUS session
For i = 1 To 128
MSComm1.Output = Chr$(85)
Next i

' send the command
MSComm1.Output = Send_String

' display reply by looping and displaying any characters
' that are received from the phone.
' The First_Flag value is used in the formatting logic.
' It ensures that a new line for each response from the
' phone does not occur on the first response (this avoids
' a blank line in your Text Box)
First_Flag = True
CheckRX:
If MSComm1.InBufferCount <> 0 Then
RdStr = MSComm1.Input
For i = 1 To Len(RdStr) Step 2
If i <> 1 Then Rcvd_String.Text = Rcvd_String.Text & " "
If CStr(Hex(Asc(Mid$(RdStr, i, 2)))) = "1E" And First_Flag = False Then Rcvd_String.Text = Rcvd_String.Text & Chr(13) & Chr(10)
Rcvd_String.Text = Rcvd_String.Text & Right$("0" & CStr(Hex(Asc(Mid$(RdStr, i, 2)))), 2)
First_Flag = False
Next i
Rcvd_String.Refresh
End If
DoEvents
GoTo CheckRX

Exit Sub

Convert_Phone_Number:
If Left$(Input_Phone, 1) = "+" Then
Phone_Number = "91"
Input_Phone = Mid$(Input_Phone, 2, Len(Input_Phone) - 1)
Else
Phone_Number = "81"
End If
Process_Digit = ""
Pad_Digits = 10
For i = 1 To Len(Input_Phone)
Process_Digit = Process_Digit & Mid$(Input_Phone, i, 1)
If Len(Process_Digit) = 2 Then
Phone_Number = Phone_Number & Right$(Process_Digit, 1) & Left$(Process_Digit, 1)
Process_Digit = ""
Pad_Digits = Pad_Digits - 1
End If
Next i
If Len(Process_Digit) = 1 Then
' We have an orphaned digit caused by
' a phone number with an odd number of
' digits, so create Fn where n = the
' orphaned digit
Phone_Number = Phone_Number & "F" & Process_Digit
Pad_Digits = Pad_Digits - 1
End If
Buf_Phone_Number = Phone_Number
If test_flag = False Then
Phone_Number = Right$(("0" & CStr(11 - Pad_Digits)), 2) & Buf_Phone_Number
Else
Phone_Number = "0A" & Buf_Phone_Number
End If
For i = 1 To Pad_Digits
Phone_Number = Phone_Number & "00"
Next i
Return

' NOTES
'
' For details on the Nokia FBUS format, jump on the web and check out
' sites such as GNOKIA. There are also other sites which talk about
' the electronics needed to interface a PC or microcontroller to
' a Nokia phone that has an FBUS interface
'
' This code assumes that you have a Form called SMS
' with the following on it:
' 1 x Text Box called 'Sent_String' with Multi-Line set to True
' 1 x Text Box called 'Rcvd_String' with Multi-Line set to True
' 1 x Command Button (which is set to run this code when it is clicked)
' 1 x Microsoft COM Control V6.0

' DISCLAIMER
' This code and the information in it has been provided at no charge, for
' non commercial use and the author disclaims all liability of any kind
' relating to any use made of it
End Sub

Private Sub SMSFail_Click()
help_string = "If you can't get an SMS to work, here are some things to try" & Chr(13) & Chr(10) & Chr(13) & Chr(10)
help_string = help_string & _
"1. Press the Test / Reset Button to test the interface (and set a different FBUS sequence number)." & Chr(13) & Chr(10) & Chr(13) & Chr(10)
help_string = help_string & _
"2. Turn the phone on and off to reset it (and the FBUS sequence number)." & Chr(13) & Chr(10) & Chr(13) & Chr(10)
help_string = help_string & _
"3. If you get 4 responses from the phone when you use the Send SMS option, but you don't receive anything on the destination phone, make sure that:" & Chr(13) & Chr(10)
help_string = help_string & _
"a) the phone can send an SMS by sending one manually; and" & Chr(13) & Chr(10)
help_string = help_string & _
"b) you are entering the correct SMSC and destination phone numbers in the correct format. "
help_string = help_string & _
"SMSC phone numbers must be in international format (eg +61411990010). Destination numbers must be in international format (eg +61411990010) or their normal format (eg 0411990010) " & Chr(13) & Chr(10) & Chr(13) & Chr(10)
help_string = help_string & _
"4. If you do not get any responses from the phone when you use the Send SMS option, follow (1), then (2) above." & Chr(13) & Chr(10) & Chr(13) & Chr(10)
help_string = help_string & _
"5. Is your phone compatible with this Utility? It has only been tested with a Nokia 3310."

MsgBox "" & help_string

' NOTES
'
' For details on the Nokia FBUS format, jump on the web and check out
' sites such as GNOKIA. There are also other sites which talk about
' the electronics needed to interface a PC or microcontroller to
' a Nokia phone that has an FBUS interface
'
' This code assumes that you have a Form called SMS
' with the following on it:
' 1 x Command Button (which is set to run this code when it is clicked)
'
' DISCLAIMER
' This code and the information in it has been provided at no charge, for
' non commercial use and the author disclaims all liability of any kind
' relating to any use made of it
End Sub

Private Sub TestReset_Click()
' declare variables
Dim RdStr As String
Dim SndStr As String
Dim i As Single
Dim First_Flag As Boolean

Sent_String.Text = "": Rcvd_String = ""
SMS.Refresh

' if the COM port is closed, then open it
If MSComm1.PortOpen = False Then MSComm1.PortOpen = True

' display what we are about to send
For i = 1 To 127: Sent_String.Text = Sent_String.Text & "55 ": Next i
Sent_String.Text = Sent_String.Text & "55" & Chr$(13) & Chr$(10)
Sent_String.Text = Sent_String.Text & "1E 00 0C D1 00 07 00 01 00 03 00 01 60 00 72 D5" & Chr(13) & Chr(10)

' refresh the form to ensure that the values are displayed
SMS.Refresh

' create the command to send
SndStr = Chr$(30) & Chr$(0) & Chr$(12) & Chr$(209) & Chr$(0) & Chr(7) & Chr$(0) & Chr$(1) & Chr(0) & Chr(3) & Chr$(0) & Chr$(1) & Chr$(96) & Chr$(0) & Chr$(114) & Chr$(213)

' Send 128 'U's' (0x55) (55D) to start an FBUS session
For i = 1 To 128
MSComm1.Output = Chr$(85)
Next i

' send the command (in this case it is the command that gets the
' the phone to return its hardware and software details
MSComm1.Output = SndStr

' display reply by looping and displaying any characters
' that are received from the phone.
' The First_Flag value is used in the formatting logic.
' It ensures that a new line for each response from the
' phone does not occur on the first response (this avoids
' a blank line in your Text Box)
First_Flag = True
CheckRX:
If MSComm1.InBufferCount <> 0 Then
RdStr = MSComm1.Input
For i = 1 To Len(RdStr) Step 2
If i <> 1 Then Rcvd_String.Text = Rcvd_String.Text & " "
If CStr(Hex(Asc(Mid$(RdStr, i, 2)))) = "1E" And First_Flag = False Then Rcvd_String.Text = Rcvd_String.Text & Chr(13) & Chr(10)
Rcvd_String.Text = Rcvd_String.Text & Right$("0" & CStr(Hex(Asc(Mid$(RdStr, i, 2)))), 2)
First_Flag = False
Next i
Rcvd_String.Refresh
End If
DoEvents
GoTo CheckRX
'
' NOTES
'
' This code has two functions:
' 1. test whether your PC - Phone Interface is working
' 2. resets the phone message sequence number if you
' just sent an SMS.
'
' Function 2 is necessary as I have not implemented any
' sequence increment logic in this utility. This means that
' once you send an SMS, you can't send another one until
' you run this code (which sends a different sequence number
' to the phone, thereby allowing you to send another SMS. This
' sequence issue occurs as as the SMS send code uses the same
' sequence number and the phone will not accept the same
' sequence number twice in a row.
'
' This code starts an FBUS session (ie sends 128 'U's (hex 55's)) to
' the phone, then sends the command to return the hardware and
' software details of the phone.
'
' All data sent to and received from the phone must be hex characters
' and the sofwtare and hardware details that come back from the phone
' will be in PDU format.
'
' IMPORTANT NOTE: the command has only been tested on a Nokia 3310
' SECOND IMPORTANT NOTE: as there can be a delay between sending
' a command and getting a response, this code loops endlessly looking
' for responses from the phone (ie it does not time out). A Nokia 3310
' will send 4 responses to this command (one short one acknowledging
' the command and 3 identical (and longer) responses containing the
' hardware and software details). You can add timeout code if you want.
' If you don't then make sure that you put a Port close command somwhere
' else in your code

' For details on the Nokia FBUS format, jump on the web and check out
' sites such as GNOKIA. There are also other sites which talk about
' the electronics needed to interface a PC or microcontroller to
' a Nokia phone that has an FBUS interface
'
' This code assumes that you have a Form called SMS
' with the following on it:
' 1 x Text Box called 'Sent_String' with Multi-Line set to True
' 1 x Text Box called 'Rcvd_String' with Multi-Line set to True
' 1 x Command Button (which is set to run this code when it is clicked)
' 1 x Microsoft COM Control V6.0
'
' DISCLAIMER
' This code and the information in it has been provided at no charge, for
' non commercial use and the author disclaims all liability of any kind
' relating to any use made of it
End Sub

Private Sub Encode_Button_Click()
' declare variables
Dim encoded_text As String
Dim i As Integer

' clear any previous values
Encoded_Msg.Text = ""
ECLength.Text = ""
ECLength.Text = ""

' display length of unencoded message
UECLength.Text = Len(Unencoded_Msg.Text)

' refresh form
PDU.Refresh

' get encoded text
encoded_text = Text_To_PDU(Unencoded_Msg.Text)

' display encoded message
For i = 1 To Len(encoded_text) Step 2
If i <> 1 Then Encoded_Msg.Text = Encoded_Msg.Text & " "
Encoded_Msg.Text = Encoded_Msg.Text & Mid$(encoded_text, i, 2)
Next i

' display length of encoded message
ECLength.Text = Len(encoded_text) / 2

' refresh form
PDU.Refresh

' NOTES
'
' This code assumes that you have a Form called PDU
' with the following on it:
' 1 x Text Box called 'Unencoded_Msg' with Multi-Line set to True
' 1 x Text Box called 'UECLength'
' 1 x Text Box called 'Encoded_Msg' with Multi-Line set to True
' 1 x Text Box called 'ECLength'
' 1 x Command Button (which is set to run this code when it is clicked)
'
' DISCLAIMER
' This code and the information in it has been provided at no charge, for
' non commercial use and the author disclaims all liability of any kind
' relating to any use made of it
End Sub

Public Function Text_To_PDU(msg)
' declare variables
Dim bin_msg_chars(128) As String
Dim return_value As String
Dim borrow_value, i, n As Byte

' default return value to nothing
Text_To_PDU = ""

' return if there is no message to encode
If Len(msg) = 0 Then Exit Function

' put the binary value of each message character
' into the bin_msg_chars array
For i = 1 To Len(msg)
bin_msg_chars(i) = Dec_To_Bin(Asc(Mid$(msg, i, 1)))
Next i

' perform the encoding (see notes below)
borrow_value = 0: n = 0
For i = 1 To Len(msg)
If i <> Len(msg) Then
If bin_msg_chars(i) <> "!" Then
borrow_val = borrow_val + 1
If borrow_val = 8 Then borrow_val = 1
n = n + 1
return_string = return_string & Right$("0" & CStr(Hex(Bin_To_Dec(Right$(bin_msg_chars(i + 1), borrow_val) & bin_msg_chars(i)))), 2)
If borrow_val = 7 Then
bin_msg_chars(i + 1) = "!"
Else
bin_msg_chars(i + 1) = Mid$(bin_msg_chars(i + 1), 1, Len(bin_msg_chars(i + 1)) - borrow_val)
End If
End If
Else
n = n + 1
return_string = return_string & Right$("0" & CStr(Hex(Bin_To_Dec(bin_msg_chars(i)))), 2)
End If
Next i

' return the encoded mesage to the calling program
Text_To_PDU = return_string

' NOTES
'
' PDU ENCODING BASICS
'
' PDU encoding is performed by taking each 7 bit character and packing
' them into 8 bit characters. If you have more than 7 characters, this results
' in a compressed form of encoding as every 7th character is encoded into
' the previous 6 characters.
'
' Encoding can be done manually by taking the characters to be encoded, writing them
' down back to front (eg hello would be written 'olleh'), converting them to
' 7 bit binary and performing the process (working left to right) set out below. In essence
' this process involves making 8 bit characters from 7 bit characters by taking bits from
' successive characters.
'
' 1. For the first character (ie the 'h'), we need 1 bit to make it an 8 bit character.
' We get this by taking it from the last bit of the next character (ie the 'e') and adding
' it to the front of the character we are processing. For this example, the bit we would
' take would be a '1'(as 'e' is 110 0101 in binary). This gives us a first encoded character
' of 1110 1000 (as 'h' is binary 110 1000) so adding the '1' we took gives us 1110 1000.
' 2. As we have taken the last bit from the second character (ie the 'e'), we need to take
' 2 characters from the following character (ie the 'l') to make an 8 bit character.
' The two would be '00' (as 'l' is 110 1100 in binary). If we add these two bits to the
' character we are processing, we get 0011 0010 (as the 'e' was 110 0101, but became 110 010
' after we took the last bit to encode our first character).
' 3. This process continues for each character until we either:
' (a) reach a point where we have taken all of the bits from the next character (eg where we
' have taken 6 bits from a character (leaving 1 bit) and then have to process that character)
' and have another character in front of that to process. To do this, we would need to take
' all 7 bits of the following character. After we do this, there is nothing left of the following
' character so it is skipped (ie we don't process it). It is not lost as it has been encoded into
' the previous character; or
' (b) reach the last character (ie there are no more characters ahead of it). At this point we
' simply leave the last character as it is (ie we do nothing to it). For our 'hello' example, the
' last character will be 0x06 (ie 6 Hex or 0000 0110 binary)
' 4. Once you have completed this process, don't forget that you have worked from right to left, but the
' encoded values must be entered into your phone from left to right. For our example we would (working
' right to left) get 0x06 0xFD 0x9B 0x32 0xE8. However, the phone would need to see E8329BFD06
'
' If you want to check a manual encoding, the working should look like this:
'
' Chr o l l e h
' Hex 0x6F 0x6C 0x6C 0x65 0x68
' Bin 110 1111 110 1100 110 1100 110 0101 110 1000
'
' Bits 110 [1111] 110 1[100] 110 11[00] 110 010[1]
' taken
'
' Result 110 1111 1101 1001 1011 0011 0010 1110 1000
' 0x06 0xFD 0x9B 0x32 0xE8
'
' reverse the order to get the form that is used to send to your phone
' and you get the result: E8 32 FD 06 (all hex)
'
' THIS CODE
'
' As Visual Basic does not have a bit shift function, the code manipulates
' the message characters by turning them into binary values and pretty much
' applying the encoding method described above.
'
' While you could perform encoding with few less lines of code using something
' like c or c++ (which has bit shift functions), there is actually not a huge
' difference in code size and this method may make the code easier to understand
' as it follows the encoding method described above.
'
' DISCLAIMER
' This code and the information in it has been provided at no charge, for
' non commercial use and the author disclaims all liability of any kind
' relating to any use made of it
'
End Function

Public Function Dec_To_Bin(dec_val)
' declare variables
Dim leading_zero_flag As Boolean
Dim i, place_val As Byte
Dim pad_zeroes As String
' logic
leading_zero_flag = True
For i = 1 To 8
If i = 1 Then place_val = 128 Else place_val = place_val / 2
If dec_val / place_val >= 1 Then
Dec_To_Bin = Dec_To_Bin & "1"
dec_val = dec_val - place_val
leading_zero_flag = False
Else
If leading_zero_flag = False Then
Dec_To_Bin = Dec_To_Bin & "0"
End If
End If
Next i
pad_zeroes = ""
For i = 1 To 7 - Len(Dec_To_Bin)
pad_zeroes = pad_zeroes & "0"
Next i
Dec_To_Bin = pad_zeroes & Dec_To_Bin
'
' NOTES
' This code converts to binary by successively dividing
' the passed decimal value by 128, 64, 32, 16, 8, 4, 2 and 1
' and testing whether each result is greater than or equal to 1
' If it is greater than or equal to 1, then it sets the relevant
' bit value to a '1'. If it is not greater than or equal to 1, then
' it sets the relevant bit value to a '0' if the leading bit flag is set.
' This flag ensures that we get one leading zero for a 7 bit character
' that starts with a '0' (eg 011 0010) and no leading zeroes for a
' 7 bit character that starts with a '1' (eg 110 1000). This is critical
' for the bit manipulation logic in the 'Text_To_PDU' routine as it has
' to have 7 bit binary values
'
' DISCLAIMER
' This code and the information in it has been provided at no charge, for
' non commercial use and the author disclaims all liability of any kind
' relating to any use made of it
End Function

Public Function Bin_To_Dec(bin_val)
' declare variables
Dim i, place_val As Byte

' logic
bin_val = Right$("00000000" & bin_val, 8)
For i = 8 To 1 Step -1
If i = 8 Then place_val = 1 Else place_val = place_val * 2
If Mid$(bin_val, i, 1) = "1" Then
Bin_To_Dec = Bin_To_Dec + place_val
End If
Next i
'
' NOTES
' This code converts the passed binary value to decimal
' by successively adding 1, 2, 4, 8, 16, 32, 64 and 128
' depending on whether the relevant binary value bit is
' a '1' or a '0'.
' The padding of preceding zeroes at the start is needed
' as the 'Text_To_PDU' routine works with binary values
' of varying sizes. The padding ensures that this logic
' always gets an 8 bit binary value
'
' DISCLAIMER
' This code and the information in it has been provided at no charge, for
' non commercial use and the author disclaims all liability of any kind
' relating to any use made of it
End Function