Note 10 - Income Taxes (Details) - Significant portion of net deferred tax asset (USD $)	Sep. 30, 2013	Sep. 30, 2012
Significant portion of net deferred tax asset [Abstract]
Net operating loss carryforwards	$ 19,576,000	$ 20,350,000
Research and development credit	2,257,000	2,206,000
Share-based compensation	526,000	600,000
Equipment	(18,000)
Patents	230,000	229,000
Accruals and other	463,000	509,000
State tax deduction	(2,000)	(2,000)
Federal AMT Credit	49,000	49,000
Allowances	127,000	184,000
Gross deferred tax asset	23,208,000	24,125,000
Less valuation allowance	$ (23,208,000)	$ (24,125,000)

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from intangible assets including goodwill.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state and local operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from property, plant, and equipment.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible alternative minimum tax credit carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible research tax credit carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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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 allowances of deferred tax asset attributable to deductible temporary differences from the allowance for doubtful accounts.

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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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