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SEE ALSO THE USB-ISA ADAPTER OPTION [here]; this is an alternative to uses power from the bus instead of an external source.
Using the SDLPT (and SUBST.COM)
CAUTION: The SDLPT needs its own power. As such, avoid “hot swapping” the SDLPT with other parallel-port devices while the system is on. I’ve destroyed two parallel ports now while doing so, before I realized this issue. Luckily only the parallel port was damaged and nothing else. The parallel port has many pins, and accidentally crossing them while an LPT-device is under power can easily cause a short. In generall, I’d say just get in the habit of shutting the system down (even remove the AC power plug) before swapping devices on your LPT port.
SDLPT means “SD-card adapted to LPT (printer) Port.” While LPT-ports are generally associated with printers (“Line Printer Terminal”), they aren’t sacredly bound to that purpose. They can be re-purpose for other general data-exchange. Heck, the LPT port was being used for adding CD-ROM support to older systems (see Backpack devices down below).
SD-cards are generally hot-swappable on modern PCs, they tend to be more forgiving with that than CF (CompactFlash) cards. And I tend to have more SD-card readers available around me than the older CF readers. You can fit a lot more on the SD card than a standard floppy disks, so the SDLPT is a nice way to get a lot of files onto your system quickly (I’ve only used 2GB SD cards, I’m not sure if larger capacity ones are supported; but that is probably a factor of the firmware on the SDLPT device being used). And doing this without risking any of your XT-IDE CF (CompactFlash) partitions. I’ve found CF’s to be less reliable at swapping them around between readers. So once a fixed-disks is set up using a CF, I tend to avoid ever moving that CF card. That said, if I really need to move a massive amount of files or a very-nested set of folders, I’ll remove the CF-card and use an appropriate reader to do so on a modern PC. But for “light duty” I prefer to use the SDLPT.
Look for something like the following (generally on eBay):
They may periodically go out of stock. But that’s the device name to search for, and a trusted vendor to contact and request info on when a new batch will be available.
Info and driver: sdlpt [Vintage2000]
The device has a jumper (J1) used to swap between two configurations. There aren’t details on the exact differences – it relates to some specifics about how the LPT port on your system works (EPP or something). Basically, if the device doesn’t work for you, try the other jumper setting (1-2 vs 2-3). But in doing so, you will also have to alternate between loading the SDDRV.SYS or SD.SYS driver. For me, SDDRV.SYS worked (and no arguments needed to be passed, but there is a /b argument that can be used to adjust the IO port that it uses if you have some exotic LPT setting).
As an example use-case, I used SDLPT to install Print Shop Deluxe. That software is on WinPCWorld and has multiple disk images. Instead of dealing with multiple disks, I just extracted each disc to an SD-card (all content into same folder). Then once the system was booted, I used the following command:
C:\>SUBST A: D:SUBST.COM is a MS-DOS utility program that substitutes the specified driver letter (A:) with D: (or whatever drive letter your SDLPT device is at, the driver will report that). Some install-software will insist on installing from a traditional disk drive letter (A or B). So, the above commands substitutes drive letter A: to your SDLPT device, then you just run INSTALL or SETUP as if from a regular A: drive. When the installer asks for the next disks, the files are there in the same folder, so just press any key and it generally proceeds as if the disks had been swapped to the next one.
That at least worked for with Print Shop Pro. This approach doesn’t always work, since some old SETUP/INSTALL programs from floppy disks are picky about the volume label matching the disk number.
As another use case, suppose I wanted to transfer over Second Reality, which is slightly larger than even a 1.44MB floppy disks (the original is about 2MB). I could use FTP if a NIC is setup, but maybe that’s not working or I don’t want to fiddle with copying from FTP transfer folders over to final install folders (or I’ve moved the system to a place that doesn’t have wired RJ45 ethernet). I can just use the SDLPT to copy it all over once, directly to where I want it. The copy over LPT is slow, but on par with what a typical disk drive copy speed would be. You can use XCOPY to copy a full directory hierarchy, like so (copy all sub-folders and empty folders, press D for directory if the target folder does not yet exist):
C:\> XCOPY D:\SDSTUFF C:\SDSTUFF /S /E