rchFallbackSet (Function)

Sets the parameters for the secondary standard (non-secure) fallback RTCU Communication Hub connection on NX32L devices. This has the same effect as setting the Fallback parameters via Device: Network: RTCU Communication Hub settings or by using the legacy sockSetGWParm function.
 

Fallback is used when the primary Server connection cannot be used, for example because of a secure connection or certificate problem. It is also used when the Server configuration is disabled. Use rchConfigSet to configure the primary Server connection.

The changes will take effect at the next call to rchOpen or at device reset. (e.g. by using boardReset).

Input:        

enable : BOOL

True to enable fallback connection, false to disable.

address : STRING (Max 41 characters)

The IP address or symbolic name of the server.

port : DINT (default 5001)

The IP port the device should use to connect to the server.

loginkey : STRING  (Max 8 characters)

The key (password) the device should use to connect to the server.

MaxConnectionAttempt : INT (default 3)

Max number of connection attempts before the network media reconnects.

MaxSendReqAttempt : INT (default 5)

Max number of send-request attempts before send fails.

ResponseTimeout : INT (default 45)

Time waiting for response in seconds.

AliveFreq : DINT (default 300)

Frequency for sending self-transactions in seconds.

The purpose of the self-transaction is to ensure a healthy two-way communication channel over the server.

For applications that are only sending data from the device to the server, this frequency can safely be increased.

Setting the value to zero will disable the self-transactions completely.

CryptKey : PTR

The key used to encrypt communication with the server.

If this parameter is not set (CryptKey set to 0), then the encryption key is not changed.

Returns:INT

Declaration:

FUNCTION rchFallbackSet;
VAR_INPUT
   enable               : BOOL;
   address              : STRING;
   port                 : DINT := 5001;
   loginkey             : STRING;
   MaxConnectionAttempt : INT := 3;
   MaxSendReqAttempt    : INT := 5;
   ResponseTimeout      : INT := 45;
   AliveFreq            : DINT := 300;
   CryptKey             : PTR;
END_VAR;

Example:

INCLUDE rtcu.inc
 
PROGRAM test;
VAR
   mobileParm : netGetMobileParam;
   rchParm    : rchFallbackGet;
   parmReset  : BOOL := FALSE;
   CryptKey   : ARRAY[1..16] OF SINT;
END_VAR;
 
// Check cellular network and RTCU Communication Hub settings
mobileParm();
rchParm();
IF mobileParm.IP <> 0 OR mobileParm.SubnetMask <> 0 OR mobileParm.Gateway <> 0 OR
   mobileParm.DNS1 <> 0 OR mobileParm.DNS2 <> 0 OR mobileParm.Authenticate <> 0 OR
   strCompare(str1 := mobileParm.Username, str2 := "") <> 0 OR
   strCompare(str1 := mobileParm.Password, str2 := "") <> 0 OR
   strCompare(str1 := mobileParm.APN, str2 := "internet") <> 0 THEN
   // Set APN and keep the default values for the others
   netSetMobileParam(APN := "internet");
   parmReset := TRUE;
END_IF;
IF NOT rchParm.enabled OR rchParm.port <> 5001 OR rchParm.CryptKey[1] <> 0 OR
   rchParm.CryptKey[2] <> 0 OR rchParm.CryptKey[3] <> 0 OR rchParm.CryptKey[4] <> 0 OR
   rchParm.CryptKey[5] <> 0 OR rchParm.CryptKey[6] <> 0 OR rchParm.CryptKey[7] <> 0 OR
   rchParm.CryptKey[8] <> 0 OR rchParm.CryptKey[9] <> 0 OR rchParm.CryptKey[10] <> 0 OR
   rchParm.CryptKey[11] <> 0 OR rchParm.CryptKey[12] <> 0 OR rchParm.CryptKey[13] <> 0 OR
   rchParm.CryptKey[14] <> 0 OR rchParm.CryptKey[15] <> 0 OR rchParm.CryptKey[16] <> 0 OR
   strCompare(str1 := rchParm.address, str2 := "gw.rtcu.dk") <> 0 OR
   strCompare(str1 := rchParm.loginkey, str2 := "AABBCCDD") <> 0 THEN
   // Clear encryption key
   CryptKey[1]  := 0;
   CryptKey[2]  := 0;
   CryptKey[3]  := 0;
   CryptKey[4]  := 0;
   CryptKey[5]  := 0;
   CryptKey[6]  := 0;
   CryptKey[7]  := 0;
   CryptKey[8]  := 0;
   CryptKey[9]  := 0;
   CryptKey[10] := 0;
   CryptKey[11] := 0;
   CryptKey[12] := 0;
   CryptKey[13] := 0;
   CryptKey[14] := 0;
   CryptKey[15] := 0;
   CryptKey[16] := 0;
   // Set RCH parameters
   rchFallbackSet(enable := TRUE, address := "gw.rtcu.dk", port := 5001, loginkey := "AABBCCDD", CryptKey := ADDR(CryptKey));
   parmReset := TRUE;
END_IF;
IF parmReset THEN
   // Reset device before the changes are used
   boardReset();
END_IF;
 
// Turn on power to the GSM module
gsmPower(power := TRUE);
netOpen(iface := 1);
 
BEGIN
   ...
END;
END_PROGRAM;