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Re: disk II repair
- Subject: Re: disk II repair
- From: Patrick Schäfer <Patrick.Schaefer@topmail.de>
- Date: 2000/03/16
- Newsgroups: comp.sys.apple2
- Organization: Forschungszentrum Juelich GmbH
- References: <8ame7j$c3s$1@SonOfMaze.dpo.uab.edu>
Dakin Williams schrieb:
> I took the cover off the drive and looked at the switch, but nothing is
> visibly wrong (ie no loose wires). The button on the switch still moves up
> and down when pressed, and makes the expected 'click.'
You can check the switch with a multimeter or just with a lamp and
battery. Disconnect the cable to the analog board first.
IIRC the WP switch goes into a buffer, then to the controller's WProt
line. Check the ULN2003 and 74LS125 chips on the analog board. You can
simply swap these chips, the drive does not have to be adjusted
afterwards.
Patrick