30 Start-up
Writing object values
The drive’s object dictionary contains 4 different types of objects:
• Constant objects: static values.
• Live objects: PDO mapped, cyclically updated, e.g. axis position value.
• Configuration objects: SDO device configuration during operation.
• Configuration objects valid on reset: most objects, applied only on reset.
Most objects are valid on reset because there are cases where related objects must
always be written in a particular order. Applying an object before another related
object could cause an error. It is not possible to define an order in the ESI or the
configuration tool so the drive defines the order internally. A valid on reset object is
not valid straight after writing, so the following procedure is required to update it.
Updating an object
The drive’s configuration file holds the currently active object dictionary values. When
Mint WorkBench’s Configuration tool or EtherCAT tool is used to change the value of
a valid on reset object, it cannot do so while the drive is operating. To change a valid
on reset object value, the following steps are performed:
• The object is modified in RAM according to the user’s changes.
• The configuration is downloaded to the drive and stored.
• The drive is reset. This causes the default values to be loaded, followed by the
configuration file containing the changed object, which overwrites the default
value.
In Mint WorkBench the menu command Tools, Store Drive Parameters performs the
necessary steps. Alternatively the command PARAMETERSAVE can be issued from
the command window.
A similar procedure must be performed when controlling the drive from an external
EtherCAT manager / PLC device:
1. Write the new value to the desired object.
2. Write the value 0x65766173 [evas/save] to object 1010:01 to store the actual
object value as a configuration value.
3. Set the NMT_GS_RESET_APPLICATION state. After passing through the
NMT_GS_RESET_COMMUNICATION state, the drive reaches the
NMT_GS_RESET_CONFIGURATION state (see page 45). At this stage the
default values are loaded, followed by the configuration file, with each object
being applied in a controlled order.
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