[help] How to add a cron entry

I need to add a cron entry to restart each 5 minutes a bin file (/usr/bin/FILE) and I don't know how.

Cron is OK (opkg install busybox-cron).

crontab -e

??????

I have the file running fine, including init.d (rc3.d) with panel start/stop manually, but sometimes need to restart. I need auto restart each 5 minutes.

Sorry my english.

Thanks

Frank

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