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Multitask function
4MELFA-BASIC IV
the flag's status. (This consideration is not necessary for task programs whose operation mode is set to
CYC (1 cycle operation) because they are executed only once.)
4.2.5 Precautions for using a multitask program
(1) Starting the multitask
When starting from the operation panel or with the dedicated input signal START, the programs in all slots
for which the "start request execution" is set in the slot parameter start conditions will start simultaneously.
When starting with the dedicated input signals S1START to S32START, the program can be started in each
slot. In this case, the line No. is preassigned to the same dedicated input/output parameter. Refer to
416, "6.3 Dedicated input/output"
for details on the assignment of the dedicated input/output.
(2) Display of operation status
The LEDs of the [START] and [STOP] switches on the operation panel and the dedicated input/output sig-
nals START and STOP display the operation conditions of programs specified in task slots for which the
start conditions are set to "START" in the corresponding "SLT*" parameter. If at least one program is operat-
ing, the LED of the [START] switch lights up and the dedicated output signal START turns on. If all the pro-
grams stop, the LED of the [STOP] switch is lit and the dedicated output signal STOP turns on.
The dedicated output signals S1START to S32START and S1STOP to S32STOP output the operation sta-
tus for each of the task slots. If it is necessary to know the individual operation status, signal numbers can
be assigned to the dedicated input/output parameters and their status checked with the status of the exter-
nal signals.
For a detailed description of assignment of dedicated input/output, please refer to
of this manual.
The status of programs whose start condition is set to ALWAYS or Error does not affect the LEDs of the
[START] and [STOP] switches. The operation status of programs in constant execution mode can be
checked using the monitoring tool of the PC support software (optional).
Mechanism 1 is assigned to slot 1
In the default state, mechanism 1 (robot arm of standard system) is automatically assigned to slot 1.
Because of this, slot 1 can execute the movement command even without acquiring mechanism 1 (with-
out executing GetM command). However, when executing the movement command in a slot other than
slot 1, the slot 1 mechanism acquisition state must be released (RelM command executed), and the
mechanism must be acquired with the slot that is to execute the movement command (execute the GetM
command).
