Note 1 - Basis of Presentation and Significant Accounting Policies (Tables)

6 Months Ended

Mar. 31, 2023

Notes Tables

Investment in Sales-type Leases [Table Text Block]

Investment in sales-type lease, gross:
2023	$	205
2024		171
2025		69
Gross investment in sales-type lease		445
Less: Unearned income		—
Total investment in sales-type lease	$	445
Current portion of total investment in sales-type lease	$	272
Long-term portion of total investment in sales-type lease		173
	$	445

Schedule of Inventory, Current [Table Text Block]

	March 31,			September 30,
	2023			2022
Raw materials and supplies	$	493		$	507
Finished goods		2,423			1,062
Less: Obsolescence reserve		(102	)		(107	)
	$	2,814		$	1,462

Fair Value, Liabilities Measured on Recurring Basis [Table Text Block]

March 31, 2023	Level 1		Level 2		Level 3		Total Fair Value
Derivative liability	$	—	$	—	$	—	$	—

September 30, 2022	Level 1		Level 2		Level 3		Total Fair Value
Derivative liability	$	—	$	—	$	—	$	—

Schedule of Share-Based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block]

	Six Months Ended
	March 31,
	2023		2022
Expected life (in years)		5.7		5.3
Risk-free interest rate		4.03% - 4.20%		1.07% - 1.87%
Expected volatility		67.61% - 67.82%		64.83% - 65.49%
Expected forfeiture rate		9.70% - 9.80%		14.65% - 15.03%
Expected exercise factor		2.01		2.02
Expected dividend yield		0.00%		0.00%

Share-Based Payment Arrangement, Option, Activity [Table Text Block]

				Weighted-		Weighted-Average
				Average		Remaining Contractual
	Options			Exercise Price		Period in Years
Outstanding at October 1, 2022		2,095,538		$	3.74		7.29
Granted		579,350			0.84		9.80
Exercised		(2,550	)		0.66		6.00
Forfeited and cancelled		(159,211	)		5.16		—
Outstanding at March 31, 2023		2,513,127		$	2.98		7.66
Exercisable at March 31, 2023		1,500,786		$	3.55		6.72

Schedule of Nonvested Share Activity [Table Text Block]

				Weighted-Average
				Grant Date Fair
Non-vested Options	Options			Value
Non-vested at October 1, 2022		931,718		$	1.57
Granted		579,350			0.41
Vested		(450,773	)		1.28
Forfeited		(47,954	)		0.81
Non-vested at March 31, 2023		1,012,341		$	0.94

Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block]

Warrants Outstanding			Wtd Ave.
Issued in Connection	Amount		Exercise Price		Life in Yrs.
Capital Raise		952,215	$	2.16		3.5
Vender Agreement		102,000	$	3.06		4.1
		1,054,215	$	2.24		3.5

Schedule of Weighted Average Number of Shares [Table Text Block]

	Three Months Ended				Six Months Ended
	March 31,				March 31,
	2023		2022		2023		2022
Denominator for basic net income (loss) per share - weighted average common shares		12,075,832		9,114,451		11,775,782		9,095,810
Effect of dilutive options and warrants (treasury method)		—		—		—		—
Denominator for diluted net income (loss) per share - adjusted weighted average common shares		12,075,832		9,114,451		11,775,782		9,095,810
Options, warrants and convertible shares outstanding during each period, but not included in the computation of diluted net loss per share because they are antidilutive		3,567,342		2,919,809		3,567,342		2,919,809