network response latency times will be extended by the amount of time required to perform an
As an example of this relationship, let’s say that we would like to access parameter “Acceleration Time #1” on an ASD connected to the
As mentioned above, direct mapping only applies when attempting to access a Modbus register that is not defined in the point database. If a specific Modbus register is defined in the point database, then the point database mapping overrides direct mapping, and the actual ASD register accessed will depend on the specific point’s configured sn number.
12.3.3 Universal Access Registers
Until now, our discussions about how to access ASD registers have primarily revolved around the method of mapping ASD registers to unique Modbus TCP/IP registers. For most control/monitoring applications, this is not a problem. However, Toshiba ASD’s contain many more accessible parameters than just the control/status parameters typically accessed during
In some applications, it may be desirable to take a “snapshot” of all configuration parameters on an ASD via the Modbus TCP/IP network, in order to create a backup file of the drive’s settings in case the drive needs to be replaced at some future time. Clearly, it would not be feasible or even desirable to create a point database that explicitly mapped all drive registers to unique Modbus TCP/IP registers. It may be possible to take advantage of the
To solve this problem, the
The two Universal Access Registers are reserved by the
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