Yaskawa Portable Control Display Unit - Manual (Page 43)

6 TEST MENU
37 NVRAM Access
01/22/96
How to Use the
View Trace / F2
Option
NVRAM Access /
Function # 994
As mentioned before, it is possible to
program up to four Trace Buffers to capture
data simultaneously. Pressing the INC or
DEC keys while viewing a Trace Buffer
will cause the PCDU to display the trace
data from the next or previous Trace
Buffer.
This option is used when entering or
editing a PAC block into a Trace Buffer is
not desired. The view option will allow
user to directly display the contents of the
Trace Buffers. Pressing the INC or DEC
keys will cause the PCDU to display the
trace data from the next or previous Trace
Buffer. If a Trace Buffer is not in use, the
PCDU will display:
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 chip. 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 or the RESET button is
pressed. This split-level approach makes it
possible to return to the last set of “stable”
parameters in NVRAM if errors are made
while fine-tuning the active drive
parameters.
Buffer 2 unused
Press INC or DEC