04.96 12 Functional Descriptions
12.25.1 Corresponding data
With the new functionality of the flexible memory configuration, the user is now in a position to
configure the memory such that it is ideally suited to the field of application of his machine
tool; this functionality is available for every HW variant of the NC-CPU. The following
characteristics can be optionally defined:
• Part program memory > 1 MB
• UMS memory > 512 KB
• Number of IKA points > 16000
• Number of measured values (axis-specific) > 0
• Memory for real axes
• Memory for extended overstore.
Furthermore, when the customer upgrades his system by replacing the 386 NC-CPU module
with a 486 SW NC-CPU module (which must feature an integrated 611D connection if he
wishes to connect a digital drive), he can decide whether he needs memory space for the
drive software. If he does not intend to connect a digital drive, this memory space can be
utilized for user data.
The same degree of freedom applies to the number of tools and R parameters to be used, i.e.
customers who require fewer tools, but use a large number of R parameters (or vice versa),
can determine the amount of memory space required for these data to suit his particular
application.
When NC machine tools are used, one or two channels are often used as machining channels
while the remaining channels are used "only" for auxiliary functions. By increasing the number
of block buffers in the block memory in the machining channels, it is possible to make these
channels "faster", i.e. it is possible to set the number of part program blocks which can be
pre-decoded during processing of a long traversing block. These pre-decoded blocks can then
be inserted in the processing sequence in the IPO cycle if required.
12.25.2 System features, boundary conditions
Compatibility
1024 KB = 1 MB (NC module with 4 MB memory) or 3072 KB = 3 MB (with 8 MB memory
configuration) are available for the data of the UMS, IKA, part programs and drive and for the
measured-value data. In addition to this storage, approximately 40 KB of memory are available
for the block buffers which are stored on a channel-specific basis, i.e. an additional 240 KB
memory capacity. Approximately 1/5 MB of memory is available for configuration purposes.
The drive software for digital drives occupies a total of 388 KB (194 KB for MSD and 194 KB
for FDD).
Users with a SINUMERIK 840C and SW version 1-3 who utilize the maximum data quantities
for the UMS, part program and IKA data and thus require a total of 1.75 MB (1 MB part
program data , 512 KB UMS data and 256 KB IKA data), must take into account that the
memory capacity is restricted to 1 MB in the case of NC modules with 4 MB storage.
When the software is upgraded from SW version 4 to the next higher version, it may be
impossible to transfer the "old" NCMEMCFG data. If, for example, the size of a block buffer
has increased and the total memory capacity available with the old SW version has been used
up, then the memory space available would no longer be sufficient. In this case, the only
possible solution is to reduce the user data area (e.g. decrease part program memory).
MD 13 (= number of TO parameters) has the same meaning as MD 60006. To ensure that
these MDs remain consistent, the contents of MD 60006 is copied over into MD 13 of the
NCK during control power-up. In this way, it can be ensured, for example, that cycles which
may evaluate MD 13 are processed correctly.
© Siemens AG 1992 All Rights Reserved 6FC5197- AA50
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SINUMERIK 840C (IA)