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Block automatically sets this bit to 1 shortly after the application program sets control bit 15 (start bit) to a 1.
If the module is a master, bit 15 is 1 if all link devices are providing input data and are ready to receive output data. The Program Block automatically resets this bit to a 0 if any link fault occurs.
If the module is a slave, bit 15 is 1 if the module is ready to exchange data with the master.
Monitor for Link Failure (bit 14)
If the module is a master, after a link fault occurs, and the specified number of retries have failed, the Program Block sets this bit to a 1. It is necessary to manually intervene to find the cause of the failure. Look at the error code in the least significant byte of the status word. Error codes are listed in the next table.
After the problem is corrected, reinitialize and restart the link. The Program Block automatically clears status bit 13 when a restart is attempted.
Monitor for an Invalid Configuration or Link Fault (bit 13)
The application program should monitor this bit to verify operation of the I/O Link.
If status bit 13 is a 1, either an invalid configuration was provided during link initialization, or a fault has occurred on an active link. The Program Block sets this bit to a 1 immediately after the problem occurs.
If the problem occurs during initialization, initialization stops. It will be necessary to enter a valid configuration into the %P registers before initialization can continue. The error code in the least significant byte of the status word will indicate what the configuration problem is.
If the module is a master and the problem is an active link fault, the Program Block automatically tries to restart the link the specified number of times.
The Program Block automatically clears this bit when the link becomes active again. If this bit continually cycles on and off, the link wiring and devices should be inspected. The application program can keep track of the number of link faults over time, and take appropriate action if too many faults occur.
GFK±0644 | Chapter 4 Programming Guide | 33 |