033

Press RESET to clear the alarm, then press PRGRM key and navigate to the program that generated the alarm. Note the line number displayed when the alarm occurred.

Locate the command causing the alarm (GOTO Nxxxx, M99 Pxxxx, or similar sequence number reference). Verify the exact N-code number being called (e.g., N100, N1000).

Use the program search function (press PRGRM > OPRT soft key > SRCH soft key, or address search) to search for the target sequence number. Verify it exists exactly as written with no extra digits or missing leading zeros.

Sequence numbers must match exactly - N100 is different from N1000 or N10. Check for spaces or special characters.

Correct either the calling address or add the missing sequence number at the appropriate location in the program. Verify parameter 3107.0 (sequence number search method) is set appropriately for your program structure.

Check if optional block skip is active (/ symbol at start of line). Press OFFSET key, check the status display, or verify the optional block skip switch on the operator panel is in the correct position.

Review the program structure for macro B conditional statements (#IF, GOTO, WHILE loops). Verify all target sequence numbers exist within the same program level and are not inside nested subprograms or external O-program calls.

GOTO and sequence number searches typically only work within the current program scope, not across subprogram boundaries.

Check parameter 3107 bit 0 (NSR) which controls sequence number search range. If set to 1, search is from program start; if 0, search is from current position forward. Adjust logic or parameter as needed.

Verify the program has not been recently edited with sections removed that contained target sequence numbers. Check program date/time stamp and compare with backup versions if available.

Identify the subprogram (O-program number) that was active when the alarm occurred. Press PRGRM key and check the program path or alarm history to determine which subprogram called M99.

Locate the M99 P____ command in the subprogram. Note the sequence number specified after the P address (e.g., M99 P500 means return to N500 in the main program).

Navigate to the main program that called this subprogram (M98 P____) and search for the target sequence number. Verify it exists after the M98 subprogram call location.

M99 P____ returns to a sequence number in the calling program. If no P address is specified, M99 returns to the block immediately after the M98 call.

Correct the M99 P address to match an existing sequence number in the main program, or add the missing sequence number at the desired return location. Test the program in single block mode to verify correct flow.