BACnetStack_SendWhoHasWithObjectIdentifierAndLimits

bool BACnetStack_SendWhoHasWithObjectIdentifierAndLimits(
  const uint32_t deviceInstanceRangeLowLimit,
  const uint32_t deviceInstanceRangeHighLimit,
  const uint16_t objectType,
  const uint32_t objectInstance,
  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);

Sends an unconfirmed Who-Has request identifying the object by Object-Identifier, restricted to a device-instance range.

BACnet reference: ANSI/ASHRAE 135-2024 clause 16.9 (Who-Has and I-Have Services).

Parameters

Parameter	Direction	Description
deviceInstanceRangeLowLimit, deviceInstanceRangeHighLimit	in	The inclusive device-instance range to query. Note: the pair 0 and 4194303 is treated as “no range” - both range fields are then omitted from the encoded request, so the query is not restricted at all. A reversed range (low greater than high), or either limit above 4194303, is refused: the call returns false and sends nothing.
objectType, objectInstance	in	The BACnet Object Identifier being searched for, carried as two parameters (see the API conventions).
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.

Returns

True if the request was sent, otherwise false.

Topic: Client requests. Declared in CASBACnetStackDLL.h.