Yaskawa DSD 406 - Manual (Page 55)

3 Operation
51 3/21/96
Non-Volatile “RAM”-Access
Non-Volatile
“RAM”-Access
Every parameter that the drive uses has three separate areas in memory
associated with it. There is a factory-set default value for each parameter which
is stored in the read only EPROM chips. There is an area in the active “RAM”
which the drive uses while it is running. There is also an area in NVRAM
reserved for each parameter. The values in the NVRAM area are copied to the
active “RAM” every time the drive is powered up . This split level approach
makes it possible to return to the last set of ‘stable’ parameters in NVRAM if
some errors are made during fine-tuning of the active drive parameters.
Function # 994 is used to perform the transfer of data between the NVRAM and
active parameter lists. The process for copying data to or from the NVRAM
parameter list is as follows:
❏ Use the ⇑
and
⇓
keys to select function # 994 from the function level. The
dual-colored LED is off during this step.
❏ Press the DATA/FCTN key to enter the "Data" level for function # 994.
The data indicator is GREEN to indicate that this function is currently being
accessed. It is possible to SAVE the current active parameters in “RAM” to
the NVRAM parameter list, or to RESTORE the current parameters from
the NVRAM parameter list to the active “RAM”. Note that a RESTORE is
the same operation that occurs inherently every time the drive is powered
up. Upon entering the data level for this function, the SCDU displays:
OFF
DATA
994
GREEN
DATA
rest
❏ The ⇑
and
⇓
keys can be used to toggle between the above display, which
indicates a pending RESTORE operation, and the following display, which
indicates a pending SAVE:
saue
DATA
RED