How to float I/O signals of EP910 devices

[Altera_Forum]

Hi, 

I work with a defense manufacturer who has qualified large number of EP910 devices. EP910 is currently not supported by Altera and not much information is available at altera.com Currently we are trying to test device characteristics of these devices.  One of them requires floating all the I/O to do leakage current test. (some devices may be already programmed) However, I do not see any information on this in the EP910 datasheet.   Can someone please point me to some Altera document that says how to program or erase a device or float its I/O signals ? I am told that it requires applying 12V to one of the pins and sending in a serial bit stream on another pin.   thanks  Anoop

[Altera_Forum]

I know that programming of EP9xx devices has been supported by many universal programmers, e.g. from HILO, and is probably still with recent products. In so far there should be no problem to erase the devices. 

 If I remember right, MAX+PLUS II can generate programming files for the classical Altera EPLDs.

[Altera_Forum]

Thanks. I do find many commercial programmers that can handle EP910 devices. 

However, if the devices being tested are already programmed, and security fuse blown, then erasing them is not an option and I would still need a way to float all I/O. Altera usually publishes low level details of how to program any device (to enable people to design their own device programmers), so that information is got to be somewhere and that is what I am trying to find.  a. Does the device float its I/O pins when erased ? b. Is there a way to float I/O pins without erasing the device ?