S7 Can Opener Tia Portal Top May 2026

| Issue | Likely Cause | Fix | |-------|--------------|-----| | TCON error 7001 | Connection ID already used | Change ID or restart CPU | | No data received | ActiveEst wrong | Server = false, Client = true | | TSEND busy forever | Send buffer > max segment | Reduce length to 1460 bytes | | Disconnect on heavy load | Keep-alive missing | Add TDISCON + reconnect logic | | CPU stops after online change | Optimized DB access conflict | Use non-optimized DB for raw buffers |

SCL implementation inside FB:

// TCON - Establish connection
IF NOT tconConnect AND NOT tconDone AND NOT disconnectReq THEN
    tconConnect := true;
END_IF;
TCON(
REQ := tconConnect,
ID := 1,
DONE => tconDone,
BUSY => tconBusy,
ERROR => tconError,
STATUS => tconStatus,
CONNECT := tconParams
);
// TSEND - Send data when buffer changes
IF tconDone AND sendRequest THEN
TSEND(
REQ := sendRequest,
ID := 1,
LEN := 100,
DATA := sendBuffer,
DONE => sendDone,
ERROR => sendError
);
END_IF; s7 can opener tia portal top
// TRCV - Receive data
TRCV(
EN_R := true,
ID := 1,
LEN := 100,
DATA := recvBuffer,
NDR => recvNew,
ERROR => recvError,
RCVD_LEN => recvLen
);
// TDISCON - Disconnect
IF disconnectReq THEN
TDISCON(
REQ := true,
ID := 1
);
disconnectReq := false;
tconDone := false;
END_IF;

Create the following screens:

Unlike the Classic version where you might drag and drop blocks, the TIA version often requires a specific workflow because TIA Portal stores data differently (inside a SQL-based project database).

Typical Workflow found in the manual:

Processing: The tool scans the project database (SQLite/SQL) and patches the block headers to remove the "Protected" flag.

Result: When you reopen the project, the lock icon is gone, and the code (networks) is visible.

Local tags (static):

| Name | Data Type | Initial | |------|-----------|---------| | tconParams | TCON_IP_V4 | – | | tconConnect | Bool | False | | tconDone | Bool | False | | tconBusy | Bool | False | | tconError | Bool | False | | tconStatus | Word | – | | tsendReq | Bool | False | | trcvReq | Bool | False | | disconnectReq | Bool | False | | sendBuffer | Array[0..99] of Byte | – | | recvBuffer | Array[0..99] of Byte | – |