Siemens 500 NIM User Manual

Page 101

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NIM Primitives

4-48

SIMATIC TIWAY I Series 500 NIM User Manual

Series 500 NIM Primitive Descriptions (continued)

Table 4-8 provides a state diagram for the various command/state
combinations.

Program Load Exception Guidelines. If you receive a data block that is
not the block you expect (the sequence number is returned in the primitive
response), it is recommended that you try to access the block again. If a
sequence error is detected, the host can try to request the data as far back
as the previous two transactions. On occasions where the upload or
download is unsuccessful, send primitive 06 (Reset Secondary Device Mode)
and restart the upload or download. Notice that Primitive 06 aborts any
upload or download operation in progress.

The attached device will enter a “time-out” period between an
upload/download response and the next primitive request. This time period
is set by default to two minutes, but can be set to different values in your
host software program. If the delay period elapses without another request,
the secondary will return to the state before the “time-out” or assume a
“neutral” state in which upload or download activity is not permitted.

Program Upload – Code 58. Availability: Release 3.0

Primitive 58 allows you to upload program and configuration data from an
attached device through the TIWAY I network secondaries. The initial
request sets the attached device into an upload mode, and the first response
(from the attached device) contains the segment mask for the segments that
are going to be transferred. From this point, each subsequent request will
automatically increment the upload request sequence number, and each
response will send the requested block of data. When the upload is
complete, the final device response will contain an “upload complete”
indicator, but no data. At this point, you should send an upload request that
contains the “end upload” command to terminate the upload.

When you send the first request, you can specify which attached device
program segments should be included in the upload. You can request
program information, data values, or “all” which returns all attached device
segments. The first response contains the MMMM field, which details the
exact segments that will be returned.

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