How SMART talks to Business Central

SMART doesn’t write directly to Business Central. Outbound work is queued in TransmissionMaster plus one of 14 child Transmission* tables. The BC Integration Worker drains those queues every 5 minutes.

This is the gold-standard pattern for outbound integration: decouple → queue → retry.

At a glance

• 15 TransmissionMaster.TransType codes and 14 child payload tables are handled today (see list below).
• Queue state lives on TransmissionMaster.Status (FK to TransmissionStatus.TransmissionStatusID): N New → C Completed (or E Error).
• The BC Integration Worker (.NET 9) polls every 5 minutes, processes TransmissionMaster rows with Status = 'N', and updates the master row when done.
• When something is missing from BC, first place to look is TransmissionMaster (join to the child table for that TransType) with Status IN ('N','E').
• A historical-sync cutoff BCLedgerSyncStartDate (2025-12-31) keeps pre-migration data out of the local ledger.

The pieces

┌────────────┐   ┌──────────────────────────────┐   ┌────────────────────┐
│   SMART    │──►│ TransmissionMaster + 14      │──►│ BC Worker (.NET 9) │──► Microsoft Business Central
│ (the apps) │   │ child Transmission* tables     │   │  every 5 minutes   │
└────────────┘   │  TransmissionMaster.Status = N │   └────────────────────┘
                 └──────────────────────────────┘
                          ▲                              │
                          │  status updates / errors     │
                          └──────────────────────────────┘

The transmission status code

Every outbound message has a TransmissionMaster row; its Status column uses the same codes as the TransmissionStatus lookup table (TransmissionStatusID). The two you’ll see most often are N (waiting) and C (completed). Child tables (TransmissionPOApprove, TransmissionLot, etc.) hang off TransmissionMasterSysID and do not carry their own status column.

All 7 transmission status codes

Code	Name	Meaning
N	New	Just created — waiting for the BC worker to pick it up.
C	Completed	Successfully posted to BC. Done.
H	Hold	Manually held by an admin (rare).
E	Error	Posting failed. See TransmissionError / TransmissionMasterErrorLog.
X	Error is Acceptable	Reviewed and waved through.
R	Resent New Transmission	Replaced by a newer transmission row.
q	BC – Not Needed	Old/legacy. The BC environment doesn’t require this transmission type.

Tip

When something doesn’t appear in BC, query TransmissionMaster (and join to the child table) — filter to Status IN (‘N’,‘E’).

Transmission queues in use

These are the only Transmission* tables the BC Integration Worker reads or writes today (Worker.cs on main). Other Transmission* tables may still exist in SmithDouglasCommunities from legacy flows; they are not in scope for this integration unless added to the worker.

See BC Integration Worker for send/receive mapping, BC API endpoints, and column-level detail.

Child table	TransType	Direction
TransmissionCommunity	comm	SMART → BC
TransmissionLot	lot	SMART → BC
TransmissionDivision	divi	SMART → BC
TransmissionVendor	vend	SMART → BC
TransmissionVendorType	vetp	SMART → BC
TransmissionVendorAddress	vadr	SMART → BC
TransmissionTerm	term	SMART → BC
TransmissionPOApprove	poap, soap	SMART → BC
TransmissionContractPostClosing	cpcl	SMART → BC
TransmissionInvoiceSubmission	inv1	SMART → BC
TransmissionEstimate	esti	SMART → BC
TransmissionLotActivityGroup	acgr	SMART → BC
TransmissionLotStatus	lsts	SMART → BC
TransmissionPaymentStatus	pays	BC → SMART

Every row also has a TransmissionMaster parent (queue control: Status, TransType, Mode, ReturnMessage, …).

Note

TransmissionPOGenerate and TransmissionLandDevBudgetActuals have models in the BCIntegration repo but no handler in Worker.cs.

TransType codes handled by the worker

ID	Name
acgr	Lot - Activity Groups
comm	Community
cpcl	Contract Post Closing
divi	Division
esti	Process Estimate
inv1	Invoice Approval
lot	Lot
lsts	Lot Status
pays	Payment Status
poap	PO Approved
soap	Service Order Complete
term	Terms
vadr	Vendor Address
vend	Vendor
vetp	Vendor Type

The historical-sync cutoff

The BC worker has a configuration flag BCLedgerSyncStartDate (currently 2025‑12‑31). Anything dated on or before that date is treated as historical and not pulled into the local ledger tables — this prevents flooding from the migration era.

Where this lives

• Worker code: BCIntegration/BCIntegration.Worker/Worker.cs.
• Queue tables: TransmissionMaster plus the 14 child tables listed above in SmithDouglasCommunities.
• Configuration: BCIntegration.Worker/appsettings.json — connection string, BC tenant/company GUIDs, Sync:BCLedgersOnly and Sync:RunOnce switches.
• Operator controls: pause/resume via the worker console (Ctrl+Shift+P to pause, space to resume).