Note 13 - Share-based Compensation - Summary of Share-based Compensation Expense (Details) - USD ($)	3 Months Ended	6 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Allocated Share-based Compensation Expense, Total	$ 145,789	$ 177,402	$ 284,250	$ 642,151
Cost of Sales [Member]
Allocated Share-based Compensation Expense, Total	5,047	5,874	11,256	11,751
Selling, General and Administrative Expenses [Member]
Allocated Share-based Compensation Expense, Total	120,133	148,600	229,455	584,097
Research and Development Expense [Member]
Allocated Share-based Compensation Expense, Total	$ 20,609	$ 22,928	$ 43,539	$ 46,303

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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