BACnetStack_SendReadForeignDeviceTable

bool BACnetStack_SendReadForeignDeviceTable(
  const uint32_t networkPortInstance,
  const uint8_t * connectionString,
  const uint8_t connectionStringLength);

Sends a ReadForeignDeviceTable BVLL message to a specified BBMD (BACnet Broadcast Management Device) to request the BBMD’s foreign device table.

Note

Requires the STACK_OPTION_NM_BBMDC (with STACK_OPTION_DATA_LINK_LAYER_IPV4 and STACK_OPTION_OBJECT_TYPE_NETWORK_PORT) build option (it turns on STACK_OPTION_BVLL_BBMD, the macro this function checks).

BACnet reference: ANSI/ASHRAE 135-2024 Annex J: J.2.7 (Read-Foreign-Device-Table) and J.5.2.1.1 (its use).

Parameters

Parameter	Direction	Description
networkPortInstance	in	The IPv4 Network Port object instance to send on.
connectionString	in	The connection string that represents the IP Address and Port of the BBMD to send the message. Example: 0xC0, 0xA8, 0x01, 0x05, 0xBA, 0xC0 is 192.168.1.5:47808. It must be exactly 6 octets; any other connectionStringLength returns false and sends nothing.
connectionStringLength	in	The number of bytes in the connection string.

Returns

True if successfully sent, otherwise false. BY DESIGN there is no hook that delivers the peer’s reply. Capture the inbound frame in your CallbackReceiveMessageForPort and decode it with BACnetStack_DecodeAs() - that is the intended and supported way to read the returned table. Note that BACnetStack_GetBDTEntry() and BACnetStack_GetFDTEntry() read THIS device’s OWN tables, not the peer’s reply to this request.

Topic: BACnet/IP: BBMD and foreign devices. Declared in CASBACnetStackDLL.h.