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kb2syd
April 27th, 2012, 04:54 AM
I have a 486 I use for making floppy images. It would be great to have a permanent 3rd and 4th floppy drive.

The primary floppy adapter is on my Adaptec 1542CF. I have tried every ISA controller I have here, setting the floppy adapter to secondary. SDRIVE loads but it doesn't see any drives. What other alternatives are there, or do I just need to load driver.sys? I tried searching on the formus, but didn't find anything concrete.

Thanks,
Kelly

Chuck(G)
April 27th, 2012, 09:59 AM
Well, secondary controller support is spotty in most software that needs to access the controller directly (e.g. I don't believe that ImageDisk will work with a secondary controller), but if you can live with just DOS access, try the attached file. Read the README.DOC for instructions.

It doesn't work for everybody (depending on how well behaved your primary controller is), but it might work for you.

Another option is to add a couple of wire jumpers on the 1542CF and use it as your primary controller for three drives. You'll have build your own floppy cable in addition and use Tulin's floppy driver for the additional drive.

Stone
April 27th, 2012, 10:12 AM
I've got a Promise VLB controller with 2 FD + 2 HD ports on it so it supports 4 floppies and 4 IDEs.

Chuck(G)
April 27th, 2012, 10:33 AM
I've got a Promise VLB controller with 2 FD + 2 HD ports on it so it supports 4 floppies and 4 IDEs.

The 4 floppy situation was very clear in the days of the 5150 and 5160 (which could support 4 floppy drives--2 internal and 2 external). When you booted DOS 1.1, the floppies would appear as A: B: C: and D: and a hard drive as E:.

That changed later, with the hard drive always being C: and the third and fourth floppies being after the hard drive partitions.

The Promise still has only a single floppy controller on it. As I mentioned before, it's possible to add a third floppy to some SCSI and ESDI controllers--and some 16-bit MFM/RLL controllers also had an external drive connector for 3 and 4. Some DTC controllers will support 4 floppy drives on a single cable by going to a "flat" scheme--all drive motors operate together and the 3rd and 4th drives must support DS2 and DS3. There are no twists in the cable.

Stone
April 27th, 2012, 11:15 AM
The Promise still has only a single floppy controller on it.... whick is not really relevent here as the OP is seeking to support 4 floppies, not tabulate the number of floppy controllers. :-)

The Promise supports...four 360KB, 720KB, 1.2MB, 1.44MB, or 2.88MB drives

Chuck(G)
April 27th, 2012, 11:19 AM
... whick is not really relevent here as the OP is seeking to support 4 floppies, not tabulate the number of floppy controllers. :-)

The Promise supports...four 360KB, 720KB, 1.2MB, 1.44MB, or 2.88MB drives


Do we know that Kelly has any or an open VLB slot? We do know that he's got an ISA slot.

Stone
April 27th, 2012, 11:23 AM
Do we know that Kelly has any or an open VLB slot? No, not at all. It was pure speculation on my part since it is a 486 and that's where most VLBs were found.

kb2syd
April 27th, 2012, 11:34 AM
No VLB. Lots of ISA and lots of PCI. This is a PICMG motherboard. I've tried SDRIVE in multiple instances. Couldn't get it to recognize any secondary controllers. I'll compare versions between what you posted and what I have.
Thanks,
Kelly

RBARDY
April 28th, 2012, 06:11 AM
to get 4 floppies in a 486 to work you need to disable the floppy support on the scsi controller and add a 4 floppy controler such as a techway 4 floppy controoler 8bit isa 3 bios address or a gsi model 11

kb2syd
April 28th, 2012, 10:06 AM
to get 4 floppies in a 486 to work you need to disable the floppy support on the scsi controller and add a 4 floppy controler such as a techway 4 floppy controoler 8bit isa 3 bios address or a gsi model 11

Since I have need of SD support, and none of the 4 floppy contollers I have seem to support that, then I guess I'm left to do a lot of cable swaps.

Chuck(G)
April 28th, 2012, 10:10 AM
SD--single density? Sure, the Compaticard IV (uses a National Semi PC8477 FDC) as well as the Sysgen Omnibridge (uses a WD 37C65) will both support FM (single-density). The DTK Mini-micro 4 will also support SD (uses a National Semi DP8473).

kb2syd
April 28th, 2012, 10:28 AM
All the cards I have that support 4 drives do no support SD. Since I need this for VCF, I'll leave it as it is for now.

Update: I found a 4 drive controller that works. Now I have 4 drives using an old LSI adapter. I even have the manual for it so I was able to disable the IDE controller on the card.