I'm having problems getting good DOS disks out of the board. I have no idea why.
I imaged my master disks of prince of Persia to SCP files. Then I took disks I scanned with scan disk on the DOS machine and verified they were OK, loaded them with the SCP file, and started having problems.
At first I could get a directory listing for the disks just fine. Then I ran SETUP and the game started installing. Both disks went through install OK. I went to run the game from my hard drive and it was complaining about files being invalid (like a setup config file being dead or even the exe failing to run). So I figured I must have had a bad disk or something. I've gone through about 8 disks, 5 of them brand new.
Things are now getting worse though. Now a lot of the disks I try just report general fail trying to get a directory. When I try to then use DOS format on them, it fails saying sector 0 is bad. Scan disk hates all the disks that come out of the SCP.
I tried to install using the original disks, and everything is fine. Scan disk reports them as OK.
I haven't touched this since Sept/Oct and just updated the program today and started trying to back things up.
The original disks I backed up and tried were both 360k and 720k
What should I do?
Clean the heads. I typically clean the heads just about every disk I image. Try using the media tester (utilities menu) to make sure the disks you are trying to write to are good.
I've gone in and clean the heads. Nothing really came off of them though.
I'm having some sort of problem with my floppies getting destroyed though. Here are my steps:
1. On MSDOS machine, take a 1.4 floppy and scan disk with surface scan which comes back as 100% good.
2. Do some operations on the floppy, all is well
3. Put it in the SCP drive and have it do a Disk Media Test
4. Get back error that says: Media failure - Track: 0, Head: 0
5. Put disk back into MS DOS machine.
6. Cannot DIR, format, or do anything with the disk. It's dead
Are these disks permanently dead?
I try this with a 720k floppy and it works every time. It only seems to hate 1.4mb floppies.
You CAN'T use the media test on a floppy you want to keep!!! It wipes the contents of the disk!
If the media test says its bad, then its bad. The test writes an 8us pulse width and then reads it back to determine how much noise there is. The allowable amount of noise is much more than a standard floppy would allow, so if it shows up as failed then the disk can not be used. If you can't format it with MS-DOS, that would also tell you the disk is bad.
3.5" disks did not fair well with time. These commonly fail, where as 5.25" disks left in the heat and warped seem to always work fine.
I know that it would be rendering the disk unusable until it's formatted. The format on the DOS machine wasn't working after I had destroyed the first track with the test on the SCP. That is what was confusing me.
A few other weird things have been happening and I think it is actually my floppy controller on the DOS machine that is misbehaving. A motherboard swap is now allowing me to at least try and format the disks that the SCP check reveals as bad. Previously it would just say (in DOS) track 0 un readable and not even let me try to format. Some that were reported on SCP as bad track 0 I can format in DOS, others I cannot. The previous controller was just failing these disks all the time.
Thanks for working through this mentally with me.
SIDE QUESTION:
I have a bunch of 5.25 disks labeled SONY MD-2D. They always fail trying to format them as 1.2MB but always succeed as 360k. They were from a lot of new floppies that were used on the C64. I just assumed that any floppy would work OK as 360 or 1.2. Was I wrong?
The reason I ask is that I have two sets of floppies. Ones that will always format correctly under DOS as 1.2 but cannot do 360, and then the reverse. Now all of the 360k disks always pass the SCP test. The 1.2mb disks always fail. On the same fence, I have 3.5 disks that are 720k and ones that are 1.4mb. The 720k disks always pass the SCP scan, and all 1.4mb fail.
In all SCP failure cases, they fail on any track scanned. When I format them in DOS, the majority have no bad sectors and a scandisk comes out clean. (few floppies here and there have some bad sectors as you might expect) This leads me to believe that the media test is doing something biased.
Only HD disks can be formatted as high density, and only low density disks can be used with low density only drives, like the 1541 used with the C64.
The media test is 100% accurate. If you are curious, look at the 1st track/head with the flux display in the analyzer. It should be a nice flat line. It could be that your drive is bad, or you are not setting the density correctly for the media type you are trying to read/write (see the pull-down menu).
Gotcha.
How do I set the expected disk type in the disk media test though? I see the combo box for the disk imager, and have been using it for that, but I didn't see a setting in the media test.
The media test uses whatever density was set prior to selecting the utilities menu. So, you can change it in the disk imager or the editor (via the pull-down menu) and then go to the disk utilities menu to run the media test. I need to add the same pull-down menu options to the utilities.