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DOS Compatible Details

We’ve been combing the woods for details about the Quadra 610, DOS Compatible Mac that we wrote about in TidBITS #202, which should ship in early 1994. One of the most useful sources of information has been the MacWEEK forum on ZiffNet/Mac (GO ZMC:MACWEEK), and especially postings from Henry Norr of MacWEEK. When combined with information from Pythaeus, the following has become clear.

The DOS card allows some sharing of information between the Mac and DOS environments, much as do SoftPC and Orange Micro’s PC card. However, the DOS Compatible card cannot display the DOS session in a Macintosh window, which would make copying text and graphics between the two environments clumsy on a single monitor system.

Switching between monitors is not instantaneous; there is a unexplained but perceptible several second delay between the two environments. Unfortunately, if you have two monitors, you cannot use the PC monitor in the Mac environment at all, which is a shame, considering the incredible utility of multiple monitor desktops.

The Quadra 610, DOS Compatible will come with 8 MB of RAM standard, and you can set the allocation between the Mac and the PC although it comes preset at 4 MB of RAM for each environment. If you install more RAM on the Mac motherboard, either environment can use that memory, but if you install RAM directly on the DOS card, then the PC environment must use that RAM and cannot share the main Mac RAM. I’d be surprised if you can reset the allocation without rebooting, although that might be a task for OptiMem from the Jump Development Group (a utility that reduces the amount of memory applications require – I’m investigating it for a review so stay tuned).

Although the card can use the Mac’s CD-ROM drive via Microsoft’s CD-ROM drivers for DOS, there’s currently no software support (and it may not even be possible in hardware) to use Ethernet via DOS, which limits the utility of the card in the big business environments that require DOS compatibility for new machines. The card, because it fits in a Quadra 610 (and presumably in the 660AV), is only 7" long; thus it may not work as easily in the longer NuBus slots in other Macs. Apple isn’t marketing to those other machines, and there’s no telling if the card requires a 68040 in the Mac or not.

Communications and printing operate as you might expect. You map the PC COM 1 and COM 2 ports (probably only one at a time) to the Mac’s modem port, so that you can use a modem from within DOS. Print jobs go to whatever printer you select in the Chooser, and if it’s a PostScript printer, you must configure your PC programs with PostScript drivers as well. If you use a QuickDraw printer, the DOS programs will print to it as if it were an Epson, the least-common denominator on the PC side of things. In either case, the DOS environment assumes it’s using a non-existent parallel port.

Like the default setup in SoftPC, the PC hard disk is a single file in the Macintosh environment. However, unlike SoftPC (at least the older version I last used) it seems that Apple has in some way implemented it as an external file system (a neat trick that makes it a window in the Finder so you can treat DOS files like Mac files). Opening the hard disk file doesn’t immediately open a window, but instead creates a new disk icon with the same name. Double-clicking on that icon opens a Finder window displaying the DOS files and subdirectories. I presume that it in some way supports the internal floppy drive, although it’s possible that Macintosh PC Exchange is involved in some way. I don’t know if you can define a Mac folder as another drive within DOS, as you can in SoftPC, but with the external file system that’s not quite as much of a problem as it would otherwise be.

One thing to keep in mind if you’re considering purchasing this system is that SoftWindows for the PowerPC should ship at the same time or shortly after the release of the PowerPC in early March of 1994. Insignia showed SoftWindows at Comdex and reports from several people indicate that it felt as fast as a 486. Insignia itself is currently talking about 33 MHz 486 speeds, and that’s on the 66 MHz PowerPC 601 chip. With the 80 MHz (or 95 MHz chip that IBM was showing) the speed of SoftWindows can only improve, unlike the speed of the DOS card. Paul Kerr of Insignia, the SoftPC and SoftWindows product manager, said that benchmarking an emulated PC against a real one is a tricky process, and some functions end up faster while others end up slower. However, it’s likely that SoftWindows will support networking and run in a Macintosh window, thus making it a cleaner fit with the Macintosh operating system. The current versions of SoftPC Professional and SoftPC With Windows suffer in comparison with the DOS card in terms of performance (Insignia claims 386 speeds), but include a pre-configured copy of Windows and are more flexible and cheaper. And of course, you can upgrade to SoftWindows for PowerPC when it ships this spring.

— Information from:
Henry Norr — [email protected]
Paul Kerr — [email protected]

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