Note 11 - Stock Ownership Plans - Weighted Average Prices of Stock Options (Details) - $ / shares	12 Months Ended
Sep. 27, 2020	Sep. 29, 2019	Sep. 30, 2018
Exercised (in dollars per share)	$ 0	$ 2.06	$ 1.42
Cancelled (in dollars per share)	2.53	2.08	2.49
Under option, end of year (in dollars per share)	$ 1.14	$ 1.82	$ 1.88

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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