You probably want to read Chapter 790 and the related statutes available here:
http://www.leg.state.fl.us/STATUTES/
790.053 Open carrying of weapons.--
(1) Except as otherwise provided by law and in subsection (2), it is unlawful for any person to openly carry on or about his or her person any firearm or electric weapon or device.
(2) A person may openly carry, for purposes of lawful self-defense:
(a) A self-defense chemical spray.
(b) A nonlethal stun gun or dart-firing stun gun or other nonlethal electric weapon or device that is designed solely for defensive purposes.
(3) Any person violating this section commits a misdemeanor of the second degree, punishable as provided in s. 775.082 or s. 775.083.
-- Nothing about knives here,
790.10 Improper exhibition of dangerous weapons or firearms.--
If any person having or carrying any dirk, sword, sword cane, firearm, electric weapon or device, or other weapon shall, in the presence of one or more persons, exhibit the same in a rude, careless, angry, or threatening manner, not in necessary self-defense, the person so offending shall be guilty of a misdemeanor of the first degree, punishable as provided in s. 775.082 or s. 775.083.