LisaList2
General Category => LisaList2 => Lisa Troubleshooting and Repair => Topic started by: Kelly king on June 08, 2025, 02:59:48 pm
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Everything was working well when all of a sudden the internal
floppy drive making noises running back a forth across the floppy.
The Floppy emu is acting strange also. I know it’s not the drive but
Something controlling it. Any ideas or how to reset drive mechanism
Controller. It’s a 2/10 should I just get a new 400k rom…no error codes
Thanks
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Any ideas or how to reset drive mechanism Controller.
... should I just get a new 400k rom…no error codes
The controller is part of the I/O board.
If the ROM were bad, then the ROM version (shown at the right end of the menubar when doing the self-test) would likely not display correctly (eg. not /88 nor /A8), and you would get an I/O Board error from the self-test. So I think, probably not the ROM.
One potential cause is a poor contact at the card edge of the I/O board or chassis. Removing and re-inserting the I/O board a couple of times may help. If it doesn't, inspect the card and socket for foreign matter/corrosion, same for the wide card edge connector that joins the motherboard to the chassis.
On the 2/10 I/O Board, the IWM is in a socket at A1 (top left corner), if a poor contact has developed in the IWM socket, I suppose it may affect the floppy without generating a self-test error. Re-seating the IWM in its socket may help.
If you've been switching back and forth between a real drive and the FEMU, perhaps something was plugged in backwards at one point... I don't recall if this is possible (perhaps all the connectors are polarized), and I don't recall if the consequences are known.
Does the I/O Board work fine other than the floppy behaviour?
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The H/88 is on corner so it’s not rom. Thanks
Everything works Lisa os and MW+II..but I was switching between the two
many time throughout the night. Use the floppy drive for scsi drive and
Then using profile and widget. I was giving the drive a workout.
The floppy emu is just flashing different menus back and forth.
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Looked at the the boards moved things around no change.
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How about replacing [the I/O Board ROM]
I think it is very unlikely to be the ROM. If the ROM were bad, it would most probably not work at all, rather than cause the FDC to generate correct but bizarre commands to the drive.
You could use BLU to dump the I/O Board ROM to verify it.
The easiest troubleshooting step is to try another 2/10 I/O Board, if you can borrow one. If you have to buy something, then perhaps first replacing the IWM is worth a try since it is in a socket and a lot less $$ than another I/O Board, but it is just a guess that it could be the issue.
edit: I thought it would be less $$ to get an IWM, but it appears they are not readily found. Perhaps and hoping one of the IWM reproduction projects will deliver in due course!
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Was able to get the WOZ chip (IWM) from John Woodall.
This did not resolve the issue with floppy drive. How hard
Is it to replace the floppy drive ribbon cable well within the 2/10.
The I/O board works perfectly.
Thanks
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How hard is it to replace the floppy drive ribbon cable
It is not difficult to replace the complete ribbon cable assembly.
The keyboard jack/power button board connector has ejector ears that you spread apart to disconnect the ribbon cable (can be done even with the top cover in place).
The motherboard card edge connector is fastened to the chassis by the two screws/nuts at either end.
If you can determine that the fault lies with the ribbon cable's floppy connector itself, you can crimp a new connector onto the cable (and cut the malfunctioning end of the cable off with scissors).
Crimping on a 20 pin connector normally requires a vice or press as well as a bit of finesse or 3 hands; ask for tips if trying it for the first time.