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, 2020	Jun. 30, 2019
Balance (in shares)	3,761,500	2,439,250
Balance (in dollars per share)	$ 0.16	$ 0.29
Granted (in shares)		1,883,000
Granted (in dollars per share)		$ 0.21
Exercised (in shares)	(80,000)	(200,000)
Exercised (in dollars per share)	$ 0.09	$ 0.12
Terminated (in shares)	(137,500)	(17,500)
Terminated (in dollars per share)	$ 0.14	$ 0.18
Expired (in shares)	(200,000)	(343,250)
Expired (in dollars per share)	$ 0.10	$ 0.14
Balance (in shares)	3,344,000	3,761,500
Balance (in dollars per share)	$ 0.16	$ 0.16
Exercisable (in shares)	2,875,533	2,863,800
Exercisable (in dollars per share)	$ 0.16	$ 0.14

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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