Commodore 2040 ,3040, 4040, 8050 Disk Drives
The manual includes all these disk drives.
(.pdf)
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Articles
4040 Disk Memory Map
This article is from the Transactor "Commodore Inner Space Anthology", pages 50-53.
8050 Disk Memory Map
This article is from the Transactor "Commodore Inner Space Anthology", pages 54-56.