Strange floppy disk problem *solved*

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grimm
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Strange floppy disk problem *solved*

Post by grimm »

I have a later 1541 disk drive with the lever and I have been using it with no problems. I ordered a manual and demo disk for it so I could complete the set. I also bought some Verbatim 2SDD floppy disks still new in the box with plastic wrap to use with the drive. I thought that is would be cool to load the VIC-20 wedge from the demo disk and try it out. It appeared to work just fine, I was able to load and run it. I noticed that the demo disk is probably newer as the help files on the disk talk about the 128.

I then tried to format and use a couple of the Verbatim disks I bought and they would not work. I could get them to format if I did it a couple of times but I could not save a file to them. At first I thought that I had bought the wrong type of floppy, but it appears from a google search that they should work. Then I thought that they might be so old that they just are bad but the date on the box was from 1993, so they are old but not ancient. :) Then I thought that maybe the wedge is the problem. I rebooted the VIC and tried to format and write to a third floppy and it worked perfectly. I then tried one of the other disks I was having problems with and it too worked great. It looks to me that the wedge was causing the problems. Is this known or normal? Or did Commodore just not support the VIC very well towards the end of the 80's? Maybe the wedge didn't load right, or the demo disk is bad? Has anyone heard or seen this happen before? Thanks,
Last edited by grimm on Sat Nov 20, 2010 6:01 pm, edited 1 time in total.
Grimm
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e5frog
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Post by e5frog »

What's this wedge you talk about?

If it messes things up, don't use it.
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grimm
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Post by grimm »

The wedge was a program that would "wedge" it self into the operating system and gives the user more commands. In this case the wedge came from the test/demo disk that was in the original 1541 disk drive box. There are two wedges on the disk, one for the VIC and another for the C64. This wedge made it easier to use the 1541 by adding additional commands to use the drive. For example instead of typing 'LOAD "TEST",8', all you had to type was '/TEST' and it would load the file. It has other commands like ">" and "@" that would give you the status of the drive and replace the usual "OPEN' and "PRINT#15" commands.

That is why I thought that this was strange, given that this particular wedge was written by Commodore. Maybe my VIC is different somehow, it is a Canadian version but that shouldn't matter, should it?
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e5frog
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Post by e5frog »

Is it a speeder as well? Perhaps you need to clean your read head or maybe something else is "on the edge" of failing.
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grimm
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Post by grimm »

Thanks e5frog, I figured it out. :) Your question about speed caused me to remember that the 1541 defaults to the C64 communication speed. You need to send the drive the following command to have it talk at VIC speed:

OPEN 15,8,15,"UI-";CLOSE 15

I did the command and re-loaded the wedge and it worked perfectly. :) So, as usual, user error. :D Still doesn't explain why the normal commands "SAVE", "LOAD" worked just fine with out the speed change? Maybe the wedge was programmed to rely on that particular communication speed and the other commands are more forgiving?

Grimm
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