The retain data can be read or written at once using P-0-1359. The list length
(MaxLen) of P-0-1359 depends on the size of the retain memory (126 or
7934 elements of 4 bytes each).
Writing is not allowed while the program is running. If P-0-1359 is
written, the data have to come from the same program (i.e., there
can be no changes to the retain data or persistent data).
During boot-up, the retain memory is transmitted to the RAM and, in case of
"Power-Fail IRQ", the data are copied from the RAM to the retain memory.
4.5
Task system
4.5.1
Definition of terms
●
Task: A task is a self-contained, basic control flow within a process.
Each task has its own state with program counter, memory stack, etc.
●
Multitasking: Multitasking is the ability to perform several tasks simulta‐
neously. The different processes are activated alternately in such short
intervals that this creates the impression of simultaneity.
●
Scheduler: A scheduler is an important element of a multitasking ope‐
rating system. According to a given strategy, it determines the order in
which ready tasks are processed. The term "scheduling" refers to the
corresponding strategies and methods with which the processing order
of the task is realized.
4.5.2
Brief description
Supported task types
Rexroth IndraMotion MLD supports up to four IEC61131 user tasks of the fol‐
lowing task types:
●
Periodic task ("cyclic" starting from 1 ms)
●
Freewheeling task
●
Event task (triggering at 1-ms intervals)
●
Task triggered by external event (external event task); two system
events were provided or this task type:
–
Event "FKM_SYNCHRONIZED_TASK": Motion task in synchron‐
ism with master communication
–
Event "CCD_SYNCHRONIZED_TASK": Motion task in synchron‐
ism with CCD
DOK-INDRV*-MLD3-**VRS*-AP02-EN-P
Bosch Rexroth AG
59/267
Rexroth IndraDrive Rexroth IndraMotion MLD (2G) as of MPx-18
Basic functions of Rexroth IndraMotion MLD
LSA Control S.L. www.lsa-control.com [email protected] (+34) 960 62 43 01