Siemens SINUMERIK 840D sl Function Manual page 1471

2.12.17 FC 10: AL_MSG error and operating messages
Description of Functions
FC AL_MSG evaluates the signals entered in DB 2 and displays them as incoming and
outgoing error and operational messages on the HMI.
The incoming signals (positive edge)
are displayed immediately in the case of both error and operating messages.
Outgoing signals (negative edge)
are only canceled immediately in the case of operating messages; in case of error messages
the messages are deleted only with the parameter "Quit" i.e. error messages remain stored
on the HMI - even if the signals no longer exist - until the user acknowledges the messages.
The "ToUserIF" parameter can be used to transfer the group signals for the feed, read and
NC start disabling signals and feed stop signal to the existing axis, spindle and channel
interfaces. The group signals are transferred to the user interface directly from the status
information in DB 2 irrespective of an interrupt acknowledgment.
1. If parameter "ToUserIF": is set to FALSE, signals are not transferred to the user interface.
2. If parameter "ToUserIF": is set to TRUE, all signals listed above are sent to the user
As an alternative to the procedure described under paragraph 2, the user can influence the
disable and stop signals without a message output by applying a disable or stop signal state
to the interface signals after FC AL_MSG has been called.
The following program illustrates this method:
CALL FC 10 (
u m 50.0;
to DB 21;
s dbx 6.0;
Basic logic functions: PLC basic program solution line (P3 sl)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
In this case, the user must take measures in his PLC program to ensure that these
signals are influenced in the interface.
interface as a group signal in each case. The user PLC program can, therefore, influence
these signals only via DB 2 in connection with a message or interrupt output. The
appropriate information is overwritten in the user interface.
ToUserIF := TRUE,
Ack := I 6.1);
//Feed disable for channel 1
//Set disable condition, reset via
//FC AL_MSG, if M 50.0 outputs the signal "0".
Detailed description
2.12 Block descriptions
197