Experimental Physics and
Industrial Control System

[email protected] · Fri, 21 Apr 2000 19:20:37 -0600 (MDT)

Dear Andrew, Ned and William
	Thanks very much for your quick responses, and on Good Friday at
that.
	I already observed the nice bumpless reboot feature of the
XVME-240 -- if I do a "soft" restart (like if you type cntl-X or hit the
"abort" button), then the output values of the XVME-240 do not change
while the EPICS system restarts.  This is great, and I wouldn't have a
problem if "soft" reboots were the only thing that ever happened...
	Unfortunately, I have to anticipate the occasional "hard" reboot
(like if the processor hangs and you have to do a power cycle or
press the "reset" button).  During a "hard" reboot, the XVME-240 is
cleared, and so I need for it to come to a failsafe setting when
everything is restarted.  In my system, the failsafe position will be "all
outputs high" -- hence I am trying to find a way to force that condition
when the database starts up.

	Of course, it would be nice to have the best of BOTH worlds:
bumpless reboot during a "soft" reset, and failsafe condition after a
"hard" reset.  That requires a method to know what kind of reboot is going
on.
	Ned's suggestion to execute explicit commands (dbpf "mybo","1") at
startup is a possibility for me, since I have automated database creation
scripts.

	Hmmm... Another idea might be for me to have my very own
definition of the bo record, with initial value "1" instead of "0".  I
think that would allow me to have the "best of both worlds" as described
above.  But now I am beginning to speculate, always a good time to end the
email.
						thanks,
							Steve

()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()
Stephen Pate		Department of Physics		office:   505-646-2135
			Box 30001, Dept. 3D		dept:     505-646-3831
			New Mexico State University	fax:      505-646-1934
[email protected]		Las Cruces NM 88003		home:     505-382-6880

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System