Note 13 - Income Taxes - Significant Portion of Net Deferred Tax Asset (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Net operating loss carryforwards	$ 10,054	$ 11,769
Research and development credit	4,712	5,479
Share-based compensation	688	538
Patents	2,331	8
Accruals and other	2,245	2,487
Allowances	280	237
Gross deferred tax assets	20,310	20,518
Equipment	(313)	(352)
Operating ROU assets	(1,066)	(1,222)
Acquired intangible assets	(2,180)	(2,592)
Gross deferred tax liabilities	3,559	4,166
Less valuation allowance	(9,378)	(8,313)
Net deferred tax assets and liabilities	$ 7,373	$ 8,039

Amount of deferred tax liability attributable to taxable temporary differences from operating right-of-use assets.

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Amount of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from accrued liabilities.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary difference from allowance for credit loss on accounts receivable.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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