Controller Setup Server Tags

Setting up server tags

Already been through the prerequisites? See prerequisites (including the note there about these English menu labels being unverified against a real screen).

S8 (main connection, always required)

MENU → SETUP → Host Comm → DETAIL → Servers → select S8:

Field	Value
Protocol	SM
Server IP	127.0.0.1
Port	18735
Start Status	START
Current Status	STARTED

Current Status can't be edited directly; press ACTION → DEFINE, then ACTION → START.

S7 (second connection, only needed when querying position while moving)

Same steps as S8, select S7, port 18736.

If you don't need S7 (most use cases don't), skip this whole section and go straight to loading the driver.

$HOSTS_CFG doesn't need editing on either

The driver writes $SERVER_PORT itself with SET_VAR when the connection is established; the only things to set by hand are the tag number, the SM protocol, and the STARTED status. Leave $HOSTS_CFG alone.

The tag number has to match the driver source

driver/mappdk_server.kl and driver/mappdk_logger.kl each hardcode a SERVER_TAG_NUM in their CONST block (8 for the server, 7 for the logger). The tag number configured on the TP has to match this number, or the socket won't open. Getting the port right doesn't mean the tag is right too, both need checking; this is the easiest thing to miss.

To use a different tag number, edit the constant in the .kl source and recompile, see driver/README.md.

Using a non-default port

18735/18736 are just the defaults; nothing in the protocol requires them specifically. Moving off the well-known ports doesn't add authentication (see the security note in the project README), but it does mean a plain scan of the default ports won't immediately find the controller.

Three places have to agree on the same number, or the socket simply won't open:

1. KAREL source: edit PORT_NUMBER in the CONST block of mappdk_server.kl/mappdk_logger.kl (right next to SERVER_TAG_NUM), recompile, and reload the new .pc onto the controller. See driver/README.md.
2. TP server config: the Port field on this page's S8/S7 setup screen above, changed to match.
3. Python side: pass the new port explicitly, FanucRobot(host=..., port=12345) in code, --port 12345 on every fanuc CLI call, or save it once with fanuc connect set --port 12345.

Mismatched port behaves exactly like a mismatched tag: WinError 10061, port not LISTENING, see verifying.

Done? Continue to loading the driver.

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Last updated: 2026-08-31