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Disks & Disk Images |
Sweet16 supports real disks, such as hard disks or floppy disks, and it also supports a concept common in emulation: disk images. A disk image is a file that contains a copy of an entire disk, be it a hard disk or a floppy disk. This image file is then used by the emulator to simulate access to an entire disk.
Disk images are the primary type of disk used in Sweet16 because they're typically faster and easier to use than real disks.
To use a physical disk in Sweet16, you must first keep in mind a few basic rules:
To mount a physical disk into Sweet16, insert it into a drive on your BeOS system (if it's a floppy). If the disk is already mounted, unmount it. If BeOS is configured to automount inserted disks, wait for it to mount, then unmount it. This is done by right-clicking (or Control-clicking) the disk icon on your desktop, then choosing the Unmount option:
Once the disk is inserted but not mounted in BeOS, you can select the Mount Physical Disk option in the File menu in Sweet16. This will produce the "Mount Physical Disks" window, which looks something like this:
This hierarchical list shows all the devices in your system, based on the driver that controls them and then the devices connected to the driver. If you click an item that can't be mounted (such as the name of a bus like "ide" or "scsi"), the item will be surrounded by a black box but won't be highlighted.
Once you've selected the device to mount, click the Mount button to mount it. If mounting is successful, the disk will show up on the emulated IIGS. If not, an alert will tell you what happened.
If you want to mount a high-density floppy disk, click the "raw" item under the floppy device type in the list.
If you want to mount a hard disk partition, locate the partition in the list by its partition ID information. This can be a bit tricky (a future version of Sweet16 will list volume names where possible in this list). For example, to mount the first partition on the ATA master 0 disk, choose 0_0 under ata:0:master:0. You can mount ATI, ATAPI, and SCSI partitions, as well as floppy disks.
By default, disks are mounted read-only (whether they're write-protected or not). If you want to be able to write to the disk, toggle off the Mount as read-only checkbox.
When you're done picking and mounting disks, click the Done button to close the window.
If you want to mount a 1.4 MB floppy disk, there's a shortcut. Just choose the "Mount Floppy" image from the File menu. This will mount the disk in /dev/disk/floppy/raw. Hold down the control key while selecting this option if you want to mount the disk read-only.
Sweet16 caches floppy disks (up to 1.4 MB). When you mount the disk, a thread is created to gradually load in the entire disk into the cache, so that future disk accesses will be faster. This thread keeps running until the entire disk is loaded into the cache, but it pauses automatically whenever you try to read or write from the disk, so that these requests are filled immediately, as fast as possible. The result is reasonably-fast floppy disk access, especially once the cache has been filled.
Additionally, disk writes are also cached, and a thread is used to write the changes to the disk gradually, over time, in the background. Be sure you don't eject the floppy from the drive until you've told Sweet16 to eject it. Then wait until you hear the ejecting disk sound effect; if you eject the disk from the drive before then, it may be corrupted. During this period, Sweet16 is writing out cached changes to the floppy.
The Disks option in the Window menu brings up a window that shows a list of all the disks you have mounted, including information about them, whether or not they're currently running, and provides some control over them.
Each disk is shown with a representative icon next to it. The disk activity indicator lights in green on SmartPort and IWM 3.5" disks (both represented by the 3.5" disk icon) when active, and the red lamp on 5.25" disk drives lights when those disks are accessed.
Next to each item in this list is the name of the image file (or physical disk device), and below that is the device number, disk image type, and disk size. You can mount disks by dragging them into this window, and you can eject disks by right-clicking one and choosing Eject from the popup menu that appears.
Disks that are locked, or are read-only, have a lock icon in the lower-right corner of the disk drive image.
If you need to create a new disk image, choose the appropriate size from the Create submenu in the File menu.
Once you select the size you'd like to create, a BeOS save filepanel will appear. Choose where you'd like to save the new disk image, then type the name of the image file. Be sure to add the suffix for the file type you want to create:
Device | Image Format | File Extension | Image File Size |
---|---|---|---|
3.5" disk | DiskCopy 4.1/4.2 | .dc | 800KB |
DiskCopy 6 | .dc6 | 800KB | |
Hard drive | .hdv | 800KB | |
Raw data | .raw | 800KB | |
Universal Disk Image | .2mg | 800KB |
Device | Image Format | File Extension | Image File Size |
---|---|---|---|
5.25" disk | DSK | .dsk | 143k |
DOS 3.3 order | .do | 143k | |
ProDOS order | .po | 143k |
Device | Image Format | File Extension | Image File Size |
---|---|---|---|
Hard disk | DiskCopy 4.1/4.2 | .dc | any (other than 800KB) |
DiskCopy 6 | .dc6 | any (other than 800 KB) | |
Hard drive | .hdv | any (other than 800KB) | |
Raw data | .raw | any (other than 800KB) | |
Universal Disk Image | .2mg | any (other than 800KB) |
Note: DiskCopy 6 files are identical in format to Raw formatted files, but Sweet16 differentiates just to help avoid confusion on the part of Mac users who might want to mount DiskCopy 6 files on their Mac desktops.
If you don't add an extension to the file's name, Sweet16 will assume that it's a Universal Disk Image file. If you get strange errors trying to access disks, odds are good that the extension isn't correct for the type of data in the file.
Once you've created the disk image, it will automatically mount on the emulated IIGS. Sweet16 has already formatted the image as a ProDOS disk, but you can erase it to another format if you want to using the Erase Disk option in the IIGS Finder.
DiskCopy 4.1/4.2 and DiskCopy 6 images can be mounted on Macintosh computers using Apple's DiskCopy software. However, because BeOS doesn't use the same file type system as the Mac, these files won't automatically be recognized by DiskCopy. You'll have to fix the type and creator codes so DiskCopy will read them.
Image Type | Type Code | Creator Code |
DiskCopy 4.1/4.2 (.dc) | dImg | ddsk |
DiskCopy 6 (.dc6) | dimg | ddsk |
Since DiskCopy 6 and Raw format files are internally identical, you can interchange the .raw and .dc6 extensions if you want to "convert" a raw image into a DiskCopy 6 image.
Once you have a disk image that you'd like to mount (whether it's one you created yourself using Sweet16 or downloaded from a web site), there are two ways you can mount it:
The disk image will be mounted in an appropriate device on Sweet16, if there are empty devices. If there aren't, an alert will explain this to you.
800KB images are always mounted in one of the two IWM 3.5" devices. 143KB floppy images (.dsk, .do, and .po formats) are always mounted in one of the two IWM 5.25" devices. Everything else is mounted in one of the eight CleverPort devices; these devices emulate the SmartPort protocol for disk accesses.
Usually you'll have disks that you want to have online when you first launch Sweet16 (such as your boot disk). Sweet16 will automatically mount any disk image files in the Sweet16 directory when you launch Sweet16. Images are mounted into appropriate devices. The first device on the slot your IIGS control panel is configured to boot from will be your boot disk.
Slot 5 will contain your IWM 3.5" disks, Slot 6 contains the IWM 5.25" disks, and Slot 7 contains your CleverPort disks.
Disk images are mounted in alphabetical order. So your boot disk should be listed first in your Sweet16 directory when sorted by name in ascending order in the Tracker.
Sweet16 will resolve links to disk images, so you can organize your disk images in folders and just put links to them into the Sweet16 directory to select your startup disks.