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Markus Barth

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  1. Thanks for the replies but am still a bit lost. My Megafile 60 has about 10-20 megs of midi and sysex data and a handful of programs from when I used it exclusively for music composition using two programs by Hybrid Arts - SMPTE Track which is a sequencing software application and Genedit which is an editor/librarian for MIDI instrument patches and sysex data. I would really like to be able to recover this data and have shipped the Megafile to a number of HD recovery companies. Most returned it saying they didn't have the software or controllers to access the data. Only one company managed to diagnose the problem. Their diagnosis was: As you may recall we discussed the options for recovery which were at that time largely unknown, being dependent on the condition of the hard drive and whether or not we have an ISA RLL disk controller chipset that supports the format on the drive. Having now examined the drive, we have found that there is a mechanical alignment issue, which prevents the drive from seeking to the desired track reliably and we have also been able to confirm that the RLL encoding, defined by the SSI 32D5321 ENDEC and 8085 firmware, is not one for which we have support in an off-the-shelf controller. These problems are not insurmountable and I am as confident as I can be at this time that it will be possible to recover data from this drive. The question is how best to proceed and I suggest that reading the drive over the ASCI interface whilst overriding the drive’s servo control during imaging is probably the quickest and most cost-effective option. It is necessary for us to spend some effort looking at the practical options for imaging the drive over the ASCI interface. The electrical specification of the ASCI interface is well documented and certainly it seems feasible to interface this to a microcontroller. It is then a case of writing the necessary code to image the drive, but this option needs to be researched in detail to be sure that it is possible. When a MFM or RLL drive with a stepper motor head actuator (positioner) is low-level formatted, the data tracks are written so that one step of the stepper motor mechanically moves the heads exactly one recorded track across the disk surface. The problem with your failed drive is that the mechanical alignment between the stepper motor, which moves the heads across the disk surfaces and the recorded tracks, has drifted over time. Now when the disk controller requests that the drive move to a specific track, the stepper motor moves the correct number of required positions, but the heads end up mechanically not lined up quite on the track, so data cannot be read. The heads in your failed drive appear to be good and it is just the alignment that needs correcting. One other approach to recovering data from your failed drive, assuming you have a fully functional Atari ST computer, would be to write an imaging program for the Atari ST. This is nothing more than a program which asks the drive to step from the very first track to the last and reads all available sectors on each track, writing the data to a file or another drive. The controller takes care of decoding the data format and checking the CRC (checksum) for the data on each sector. Theoretically, provided that you can help the drive to see track 0, which it needs to do at least once after power on, an imaging program with sufficient read-retries will allow you time to manually tweak the head position for each track as it runs and so read all the data on each and every track. They wanted over £750 to recover the data and would still charge me at least £275 even if they were unsuccessful in recovering any data. That's way out of my budget. I was hoping to find someone in Atari land who might have the expertise/willingness to help me out with this. The Megafile 60 is the faulty disk. I also have a Megafile 30 that is working fine. Ideally, if someone were to be able to provide a utility that could read the Megafile 60 and copy over the files onto the Megafile 30, I would be able to recover what I wanted. The problem is that I don't have any program or utility that can read the Megafile 60. I am hesitant to try and find/buy a working Megafile 60 but they are few and far between and quite expensive only to find that the fix doesn't work. Then I am stuck with more gear. Alternatively, I'd be happy to send the Megafile to someone who has the hardware/software to create a disk image on a PC and save to an SD card. Assuming the programs and data are recovered, then all I need is an UltraSatan which I can then use as my main hard drive. Sorry to go on for so long but I figured presenting as much background as possible would give me the greatest chance of finding someone who can help. By the way, I am in London not the USA. Cheers Markus
  2. HI: Questions: I notice a second D19 jack on the back of my Megafile 30 and 60 hard disks. Is it possible to daisy chain them together by connecting the OUT jack of the primary drive to the IN jack of the second megafile using the same 19 pin cable that connects a megafile to the Atari 1040ST? And if the above is possible, is there disk imaging software for these drives that works on a 1040ST running TOS 1.04 that would enable me to do a disk image from one drive (which has issues with head alignment) to the other drive in order to save the data that is on the first drive? Has anyone written an Atari utility that can help? Thanks in advance Markus
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