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Altera_Forum's avatar
Altera_Forum
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16 years ago

Master reset and nconfig

Hi, We have a deisgn with iMx27 and 3 cyclones. The 3 have their FPP configuration pins connected to the iMX. During power on reset, the iMX has to hold low the 3 FPGAs until is ready to send c...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

As soon as nCONFIG is low the FPGA will enter configuration mode.

All pins will be tristate, execpt those used for configuration.

So if your external reset signal enshures that all FPGAs nCONFIG will be 0 then you should be on a safe side.

If you need to route the external reset to nCONFIG (in any kind) depends upon your application if you want to have your FPGA in a well known safe state or if you want to keep them doing their job until they get reconfigured.

Regards.