BACnetStack_SendUnconfirmedTextMessage

bool BACnetStack_SendUnconfirmedTextMessage(
  const uint32_t sourceDeviceInstance,
  const bool useMessageClass,
  const bool useNumericMessageClass,
  const uint32_t messageClassUnsigned,
  const char * messageClassString,
  const uint32_t messageClassStringLength,
  const uint8_t messagePriority,
  const char * message,
  const uint32_t messageLength,
  const uint8_t * connectionString,
  const uint8_t connectionStringLength,
  const uint32_t networkPortInstance,
  const bool broadcast,
  const uint16_t destinationNetwork,
  const uint8_t * destinationAddress,
  const uint8_t destinationAddressLength,
  const uint8_t messageClassStringEncoding,
  const uint8_t messageEncoding);

Sends an unconfirmed UnconfirmedTextMessage request, delivering a text message with no acknowledgment (see BACnetStack_SendConfirmedTextMessage() for the confirmed variant).

Note

Requires the STACK_OPTION_DM_TM_TEXT_MESSAGE build option (it turns on STACK_OPTION_TEXT_MESSAGE, the macro this function checks).

BACnet reference: ANSI/ASHRAE 135-2024 clause 16.6 (UnconfirmedTextMessage Service).

Parameters

Parameter	Direction	Description
sourceDeviceInstance	in	The device instance originating the message.
useMessageClass	in	Whether message-class [1] is sent at all - it is OPTIONAL per cl. 21.3.3.
useNumericMessageClass	in	When useMessageClass is true, selects which CHOICE arm of message-class [1] is sent: true for the numeric [0] Unsigned arm (messageClassUnsigned, which may legally be 0), false for the character [1] CharacterString arm (messageClassString, messageClassStringLength). Ignored when useMessageClass is false.
messageClassUnsigned, messageClassString, messageClassStringLength	in	The message class value: messageClassUnsigned when useNumericMessageClass is true, otherwise the string.
messagePriority	in	The BACnetMessagePriority of the message: normal = 0, urgent = 1. The value is not validated; any other number is encoded as it is.
message, messageLength	in	The text message content and its length.
connectionString, connectionStringLength	in	The datalink address to send TO (the destination) - not the local address to send from. For IPv4 this is 6 bytes: 4 octets of IPv4 address followed by 2 octets of port, big-endian (e.g. 0xC0,0xA8,0x01,0x05,0xBA,0xC0 = 192.168.1.5:47808; see BACnetStack_SendRegisterForeignDevice() for a worked example); on BACnet/IPv4 the stack refuses to send to a connection string of any other length, except that a broadcast from a device registered as a foreign device goes to its BBMD and does not use the connection string. MS/TP and BACnet/SC use a different connection-string shape; see their respective Set/Send exports.
networkPortInstance	in	The Network Port object instance to send the message on, or BACNET_NETWORK_PORT_DEFAULT (4194303) for the default/single port.
broadcast, destinationNetwork, destinationAddress, destinationAddressLength	in	broadcast selects a broadcast or a unicast where the data link has the choice: on BACnet/IP an Original-Broadcast-NPDU or an Original-Unicast-NPDU (a broadcast from a device registered as a foreign device goes to its BBMD as a Distribute-Broadcast-To-Network); on BACnet/SC the broadcast VMAC; on MS/TP it is ignored and connectionString decides. destinationNetwork 0 keeps the message on the local network; 1 to 65534 routes it to that network, to the device whose MAC address is destinationAddress/destinationAddressLength or, with NULL and 0 there, to every device on that network; 65535 is a global broadcast to every network.
messageClassStringEncoding, messageEncoding	in	The character set (cl. 20.2.9) messageClassString/message are encoded in: 0 = UTF-8, 1 = IBM/Microsoft DBCS, 2 = JIS C 6226, 3 = ISO 10646 (UCS-4), 4 = ISO 10646 (UCS-2), 5 = ISO 8859-1.

Returns

True if the request was sent, otherwise false.

Topic: Client requests. Declared in CASBACnetStackDLL.h.