Epson SMD-340 / Discovery cart

[+remowilliams]

I've got a few Epson SMD-340s that I've used as floppy drive replacements in STs. They work great out of the box, reading protected disks, running the pasti imager, etc. All standard ST DS/DD drive type stuff.

 

I noticed that when I tried my Discovery cart that while the drives can write MFM disk images created previously (on other drives) on the DC, they cannot seem to create disk images properly. When I try to image disks to a file, the DC software reads the disk but when the file is written it's always some really small incorrect size (<20K). Anyone have any idea? Is it because the 340s are HD drives?

[ppera]

Likely. I have couple SMD380. Wanna swap ?

Edited July 9, 2008 by ppera

[ijor]

Are you trying to write an image file to the same drive that you read the protected disk?

 

If so, it is possibly a media change detection issue. As we discussed several times on the forums, PC drives are 99% compatible, not 100%. One of the main issues is the behavior of the write protect signal.

 

Depending on the TOS version (I don't remember the exact behavior in each TOS version), you might workaround by inserting and removing the disk multiple times. When you are prompted to insert the destination disk, insert it once write enabled, once write protected, and lastly write enabled again. This might help.

 

Or use two drives. Or, use a hardisk. Or, if you have enough RAM, use a ramdisk.

 

Or use a hardware fix for the drive. I think Ppera posted one.

[+remowilliams]

Are you trying to write an image file to the same drive that you read the protected disk?

No, I'm trying to create new MFMTEMP images using the 340s and the DC, which isn't working. I can correctly write images on the 340s that were created with a standard ST drive.

 

If so, it is possibly a media change detection issue. As we discussed several times on the forums, PC drives are 99% compatible, not 100%. One of the main issues is the behavior of the write protect signal.

Hmm, I thought about the write protect detection issue but dismissed it as the Pasti imager seems to work fine on the 340s. Though even if the write protect line wasn't working correctly, wouldn't a drive be able to read a disk and create a DC image?

 

I do have other PC drives that will in not work in Pasti because of the write protect sense issue.

 

Or use two drives. Or, use a hardisk. Or, if you have enough RAM, use a ramdisk.

I'm using a Satandisk for the hard drive that is storing the DC images.

[ijor]

No, I'm trying to create new MFMTEMP images using the 340s and the DC, which isn't working. I can correctly write images on the 340s that were created with a standard ST drive.

 

I'm using a Satandisk for the hard drive that is storing the DC images.

 

So what you are doing is to read a protected disk with the Epson drive, creating an MFMBTEMP image file in the SatanDisk?

 

If so, please try somehow without the SatanDisk. Disconnect the SatanDisk, boot from floppy and try a ramdisk, or disk to disk, etc. It is possible that there is a conflict between the DC software and HDDriver.

 

If it that doesn't help, please send me the tiny MFMBTEMP image.

 

Hmm, I thought about the write protect detection issue but dismissed it as the Pasti imager seems to work fine on the 340s. Though even if the write protect line wasn't working correctly, wouldn't a drive be able to read a disk and create a DC image?

 

That was a different issue. In that case it was about a write protect detection. But here I was talking about a media change detection, that is only indirectly related to the write protect signal.

 

Anyway, I misunderstood what you were trying to do. So it shouldn't be relevant.

Edited July 9, 2008 by ijor

[+remowilliams]

So what you are doing is to read a protected disk with the Epson drive, creating an MFMBTEMP image file in the SatanDisk?

Correct.

 

If so, please try somehow without the SatanDisk. Disconnect the SatanDisk, boot from floppy and try a ramdisk, or disk to disk, etc. It is possible that there is a conflict between the DC software and HDDriver.

I'm actually using ppera's HD driver and BigDOS for FAT compatibility. I'll try booting another SD card with HDDRIVER on it, as well as a real HD and floppy without the Satandisk. Though, if I swap out the floppy drive in the ST with another 'compatible' drive I can create MFMBTEMP images correctly using the same Satandisk/ppera HD/BigDOS combo.

 

Here's the tiny MFMBTEMP image.

 

MFMBTEMP.zip

[ijor]

Though, if I swap out the floppy drive in the ST with another 'compatible' drive I can create MFMBTEMP images correctly using the same Satandisk/ppera HD/BigDOS combo.

 

I see, this probably means it is not a software conflict. I'd try with a clean boot anyway, just to make sure.

 

If a clean boot doesn't help (it probably won't), and assuming you don't have any "HD" hardware mod for using HD disks; then it seems that those drives have an electrical incompatibility. It is difficult to be sure without seeing the signal with a scope.

[+remowilliams]

If a clean boot doesn't help (it probably won't), and assuming you don't have any "HD" hardware mod for using HD disks; then it seems that those drives have an electrical incompatibility. It is difficult to be sure without seeing the signal with a scope.

Yeah, not using any HD floppy mods, I just want nice DSDD replacements.

 

One other thing I'll add - it seems that there are also issues with the 340 when using the Spectre GCR cart. A few times the drive passed the GCR tests, but many times it failed the GCR format/verify test.

[ijor]

One other thing I'll add - it seems that there are also issues with the 340 when using the Spectre GCR cart. A few times the drive passed the GCR tests, but many times it failed the GCR format/verify test.

 

Interesting. This supports the theory that it's an electrical issue.

 

The question is why it doesn't seem to affect the FDC at all. Again, a scope would probably be very helpful.