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Floppy emu questions (for use with my Plus)

tanaquil

6502
I am thiiiiiiiis close to springing for a Floppy-Emu, but I just have a few questions about how it works in practice. I thought about posting to Peripherals, but I don't read that board nearly as much as I read this one.

The manual on BMOW's site says that .img, .image and .dsk images all work, but that RAW (.dsk) images are ideal. What is the best tool to use to produce or convert-to .dsk images? I create some disks in mini vmac, and I've also made disks using DiskDup+; they both have .dsk extensions but look different in OS X, so they must have different file/creator ids. Also, are both Disk Copy 6 and Disk Copy 4.2 images supported, or only the latter? I have seen DC 4.2 images with both .image and .img codes. Basically, I'm wondering if there is one ideal set of file/creator codes that I should apply to all the disk images that I want to use with the EMU. I have a good variety of working classic systems ranging from 6-7-9 as well as modern OSX, so I'm game for using whatever disk utility is most recommended.

How does the Floppy EMU handle navigating through folders? Ideally, I'd like to have a small set of folder categories (e.g. Apps, Games, System). In the promo video it looks like there are folders on the SD card, but I'm wondering if they are easy to navigate.

I have found that some games don't play well under emulation (in mini vmac). Does this affect floppy-emu images, or is the Mac completely unable to detect that it is not reading a real floppy? Do games run at the same speed they would run if a real floppy were loaded?

What accessories do you use to plug the SD card into your modern machine to load up software? I have a 2011 MacBook Pro, and I have literally never used any kind of compact card with it. My machine seems to have a slot in the side, but I have no idea what would fit into it (it looks too big for SD). I don't mind buying a compact card reader, so hit me up with your recommendations.

I feel like I'm getting ready to bring a pet home...

 
I don't know anything about floppy emu, but at least regarding the data format you can create .dsk images using HFVExplorer fairly easily. As far as I know it runs on Windows only, however. If you are using a modern Mac to do this work then you might try looking at this site for some pointers:

http://www.gryphel.com/c/image/

Instructions on how to use HFVExplorer are also provided on that page.

 
How does the Floppy EMU handle navigating through folders? Ideally, I'd like to have a small set of folder categories (e.g. Apps, Games, System). In the promo video it looks like there are folders on the SD card, but I'm wondering if they are easy to navigate.
Navigating is easy-- "Prev" button for up, "Next" button for down, "Select" button to select. To navigate to the parent directory, select the ".." option at the top of the list. The only thing I recommend against is putting a lot of files in one folder-- beyond a couple dozen files, the Emu will stall for several seconds while it builds the directory list. It's not cached, either.

I have found that some games don't play well under emulation (in mini vmac). Does this affect floppy-emu images, or is the Mac completely unable to detect that it is not reading a real floppy? Do games run at the same speed they would run if a real floppy were loaded?
The Emu shouldn't affect how the games themselves are emulated. The most outlandish thing the Emu does is emulate an HD20 with a capacity different from its original 20MB size. I suppose games that are hardcoded to expect a floppy of a certain size might have problems, but I have not encountered such applications. The image formats supported by the Emu do not support some copy-protection schemes used by early Macs, so you might run into problems there. Generally if Disk Copy 4.2 can successfully make an image of your source disk, the Emu can serve it perfectly. The speed of the Emu is limited primarily by the speed of the Mac's floppy interface, so speed is comparable to an actual external floppy drive.

What accessories do you use to plug the SD card into your modern machine to load up software?
I use a cheap USB stick with a microSD slot on one end. Works great with my 2010 MBP.

 
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A lot of my floppy images do not work on the FloppyEmu, I'm assuming they are in Disk Copy 6 format as the FloppyEmu specifically says it only supports raw and DC4.2 formats.

To use these images I had to use a Basilisk II VM with System 7.5.5 and Disk Copy 6 to convert them to Disk Copy 4.2 format. It's a bit frustrating to be honest.

 
I could look at adding DiskCopy 6 support, if there's a lot of interest. Or a stand alone DC6 to DC42 converter program. To be honest I never really investigated it, beyond seeing that it looked more complicated than DiskCopy 4.2, and all the other tools and emulators I've played with use DC42 or just raw disk images. 

The reason raw disk images are preferred over DiskCopy 4.2 images is that DC42 images have a small header tacked onto the front, which causes the alignment of each 512 byte block in the file to span two 512 byte blocks on the SD card. To read a single logical block from the file, the device must perform two reads from the card. Same for writes. This cuts the I/O bandwidth in half. In practice, it doesn't make much difference except for when writing, because the floppy interface isn't very fast anyway.

As far as file/creator codes go, there are none, because the disk image files are stored on the SD card as FAT32 (Windows), not Macintosh files. I use Mini vMac (cross platform) and HFVExplorer (Windows) most of the time for creating the raw disk images.

The slot in your MBP is almost surely a full-sized SD card slot. Floppy Emu Model A uses full-sized SD cards, Model B uses mini-sized cards like those found in many mobile phones, but the cards are normally sold with a full-sized adapter included. 

Blitter, thanks for pointing out the stall problem with large directories - I'll see if I can do anything to improve that. 

 
Thank you, everyone, this was very helpful! Trigger pulled.

Thanks especially to BMOW for a very clear explanation.

Cool site, kingchops, I bookmarked and will definitely visit again.

I'd still be happy to hear more practical advice from anyone who uses a floppy emu regularly.

 
I could look at adding DiskCopy 6 support, if there's a lot of interest. Or a stand alone DC6 to DC42 converter program. To be honest I never really investigated it, beyond seeing that it looked more complicated than DiskCopy 4.2, and all the other tools and emulators I've played with use DC42 or just raw disk images. 

What format are the images in on the Apple Legacy Software CD-ROM? None of those were detected by my FloppyEmu until I ran them through conversion in DiskCopy on Basilisk II. 

I might have been missing something as I'm new to the world of 68K Macs, but I just got an SE/30 and FloppyEmu and I couldn't find floppy images for System 7.5.3, for example, outside of the DiskCopy 6 version (assuming) that's on the Legacy Software CD-ROM. I feel like supporting this format would be great for the FloppyEmu, especially as it's not easily apparent (e.g. through file extension) what format the image is in. I have to copy them to the SD card, then boot the system with the FloppyEmu, to see if the image is even in the right format.

 
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Would the fact that Disk Copy 6 images rely on resource fork data be a problem? As I recall, this is an issue with DC 6 images more than with DC 4.2 images (the latter will often survive improper stuffing and transportation over non-compatible platforms, DC 6 images won't).

It's interesting that Floppy EMU doesn't require resource fork data at all. My computer lizard brain is firmly stuck in 1992, and is convinced that any failure to preserve resource forks will result in utter ruination.

Now I understand why the images I've been creating in mini vmac (using the "blanks" supplied for use with the emulator) have been making files that have no type/creator code data. Weirdly, they do have a custom icon and my Mac thinks they're "5 inch disks." Mysteries!

 
What format are the images in on the Apple Legacy Software CD-ROM? None of those were detected by my FloppyEmu until I ran them through conversion in DiskCopy on Basilisk II. 

I might have been missing something as I'm new to the world of 68K Macs, but I just got an SE/30 and FloppyEmu and I couldn't find floppy images for System 7.5.3, for example, outside of the DiskCopy 6 version (assuming) that's on the Legacy Software CD-ROM. I feel like supporting this format would be great for the FloppyEmu, especially as it's not easily apparent (e.g. through file extension) what format the image is in. I have to copy them to the SD card, then boot the system with the FloppyEmu, to see if the image is even in the right format.
I just checked the Legacy CD. My mac identifies all the images as "NDIF Disk Image", which I think is the usual term for a Disk Copy 6 image. Quick Change (just discovered this little utility, love it!) identifies type and creator code as "rohd" and "ddsk".

[it doesn't surprise me that 7.5 images are in this format, since by that time Disk Copy 6 had replaced DC 4.2 as far as Apple was concerned, but why on earth would you make a disk labeled as "System Tools 512Ke" in that format? I guess they assumed technicians would be burning floppies while working on more modern hardware??]

My Plus install of mini vmac didn't recognize any of the NDIF images at all - I guess mini vmac can't read DC 6 images either. I always thought those disks that showed up with "v" on them (the ones you can make with HFS Disk Maker) were DC 6 images, but I guess they're not. Anyway, I don't know your setup, but I suppose you could test your images in vmac before loading them onto the EMU.

 
I just checked the Legacy CD. My mac identifies all the images as "NDIF Disk Image", which I think is the usual term for a Disk Copy 6 image. Quick Change (just discovered this little utility, love it!) identifies type and creator code as "rohd" and "ddsk".
I'm pretty sure OS X is just going by the file extension there. 

All of my files that end in "img" say "NDIF Disk Image" but if I rename them to end in "image" they switch over to "Disk Copy 4.2 Disk Image" and vice versa

 
I'm pretty sure OS X is just going by the file extension there. 
Ah, I bet you're right. But some internet searching seems to confirm that rohd/ddsk is indeed the type/creator code for DC 6.

 
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Would the fact that Disk Copy 6 images rely on resource fork data be a problem? As I recall, this is an issue with DC 6 images more than with DC 4.2 images (the latter will often survive improper stuffing and transportation over non-compatible platforms, DC 6 images won't).
Ah, now that you mention it, I think that was the reason. Basically there is no good way to store or represent a DC6 image file under FAT32, just as there's no good way to store a classic Mac application program under FAT32 without sticking it into another data-only container like StuffIt or MacBinary or BinHqx. 

 
Thank you, everyone, this was very helpful! Trigger pulled.

Thanks especially to BMOW for a very clear explanation.

Cool site, kingchops, I bookmarked and will definitely visit again.

I'd still be happy to hear more practical advice from anyone who uses a floppy emu regularly.
You will love it! I repair old Macs and the FloppEMu was my best purchase last year. Makes troubleshooting systems and simply playing old games so much easier.

 
Ah, now that you mention it, I think that was the reason. Basically there is no good way to store or represent a DC6 image file under FAT32, just as there's no good way to store a classic Mac application program under FAT32 without sticking it into another data-only container like StuffIt or MacBinary or BinHqx. 
Ah, that's a bummer. Perhaps you could look into what it takes to make a converter for a modern OS?

 
Anyone know of a utility or a hack to batch-convert DC 6 images to DC 4.2 and/or DiskDup .dsk images? I know it can be done by opening each file individually in DC 6 or DiskDup, but dang, slow.

It's easy to batch-change type/creator codes, but that does no good if the nature of the image isn't changed. 

 
Ah, that's a bummer. Perhaps you could look into what it takes to make a converter for a modern OS?
Maybe I'm missing something, but I actually think that's not possible, because there's no way to even get a DC6 file onto a modern OS in order to convert it. By the time you've copied the file to your Windows or OSX machine in order to run the hypothetical converter, the file would already be foobared by losing the resource fork. The only way around that would be if your modern OS could mount an HFS volume directly in order to read the DC6 file. Otherwise the converter tool would need to be something that runs under the classic Mac OS, and Disk Copy 6 is already that tool. Granted, that will be tedious if you have a lot of image files to convert. Offhand I don't know of any batch converters. Could you use Applescript to automate it somehow?

 
HFS+, the default filesystem for OS X, still uses resource forks. All of the aforementioned System 7.5.3 Disk Copy 6 images I'm converting through Basilisk II are going through an HFS+/OS X system. I mount the Apple Legacy Software CD-ROM, copy the .IMG files to a folder titled "BasiliskIIShare" on my OS X system. Then I set that folder to appear as a network share in Basilisk II. I boot up System 7.5.5 in Basilisk II, launch Disk Copy 6 (an application which is also stored on the network share as well, and functions fine), and convert the file to a DC4.2 file. I then copy the new image file from the BasiliskIIShare folder to the FloppyEmu SD card. 

 
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