Note 12 - Equity Transactions and Stock-based Compensation - Summary of the Company's Stock Option Activity, and Related Information (Details) - $ / shares	12 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Balance (in shares)	3,916,666	3,344,000
Balance, weighted average exercise price (in dollars per share)	$ 0.26	$ 0.16
Granted (in shares)	764,700	770,000
Granted (in dollars per share)	$ 0.85	$ 0.66
Exercised (in shares)	(146,333)	(157,334)
Exercised (in dollars per share)	$ 0.23	$ 0.15
Terminated (in shares)	(44,700)	(3,333)
Terminated (in dollars per share)	$ 0.53	$ 0.21
Expired (in shares)	(46,400)	(36,667)
Expired (in dollars per share)	$ 0.47	$ 0.21
Outstanding as of June 30, 2021 (in shares)	4,443,933	3,916,666
Outstanding as of June 30, 2021 (in dollars per share)	$ 0.36	$ 0.26
Exercisable at June 30, 2021 (in shares)	3,524,500	3,114,099
Exercisable at June 30, 2021 (in dollars per share)	$ 0.26	$ 0.19