Delta Tau PMAC Pack, Hardware Reference Manual

Page: 36 / 121

PMAC-Pack
Getting Started 25
Figure 2-4. Flag Input in A Sinking Configuration Figure 2-5. Flag Input in Sourcing Configuration
Home Flag Signal (Home)
As with the Limit inputs discussed above, a home switch can be wired between the Home Flag Input pin
(HOME is pin 5 of each “Flags” port) and Fault Return (FRET). The switch may be normally open or
normally closed; open is high (1), and closed is low (0). The polarity of the edge that causes the home
position capture is programmable with Encoder I-Variables 2 and 3 (I902 and I903 for HOME1). PMAC-
Pack’s HOME inputs may be wired as sinking or sourcing and support operation at 12 or 24 V DC.
Software Setup of the Controller
PMAC has a large set of Initialization parameters (I-variables) that determine the personality of the card
for a specific application. Many of these are used to configure a motor properly. Once set up, these
variables may be stored in nonvolatile EAROM memory (using the
SAVE
command) so the card is
always configured properly (PMAC loads the EAROM I-variable values into RAM on power-up).
Connect power to your PMAC-Pack only. (At this time, do not power your amplifiers.) Run your PMAC
Executive Program on the PC. The value of an I-variable may be queried simply by typing in the name of
the I-Variable. For instance, typing
I900<CR>
causes the value of the I900 to be returned. The value
may be changed by typing in the name, an equals sign, and the new value (e.g.
I900=3<CR>
).
Alternatively, you may use the I-variable pages (under the
Configuration
menu) to view and change these
variables in a more user-friendly fashion.
Note:
If you change any I-variables during this setup, you must use the SAVE command
before you power down or reset the card, or you will lose the changes that you
have made.