I have an NI488.2 GPIB that has been running an old Camac crate for the last 4 years. It has always been on the edge timing wise, the Camac is quite slow, but has been reliable until now. During routine operations the communications broke down. It worked one moment and failed the next and has not worked since. It looks like the PCI-GPIB card is way ahead of the camac. Loading up the system with NiSpy and my own monitor slows the connection down enough to get some function back. What could cause the timing to change unexpectedly and without intervention? I have slowed the bus timing to 2usec to no avail. Can I get it any slower? It's not the hardware. I just replaced the GPIB card with a new one with the same results. Your help is appreciated.
. Apparently the old GPIB card had indeed failed. The new card fixed the problem after rebooting the Camac. I have never had a GPIB card go down in 20 years.