PDA

View Full Version : Copy II PC Board FDD Support



Shadow Lord
June 14th, 2011, 02:56 PM
Hello All,

This is something I've been wondering about: What FDD are supported by what Copy II PC Boards? In my simplified view of things the original non-deluxe board only supported 360KB drives. The deluxe board expanded support to HD drives (1.2 and 1.44 MB drives) and I am assuming this is true of the EOB board? Is this correct?

Also what would happen if you put a 1.2MB FDD on the original Copy II PC Board? I.E. if I have a 1.2MB drive and a 360KB drive on the same floppy cable and use a copy II PC board will it work with both drives or only the 360KB? Will it cause problems with using the 1.2MB floppy drive just as a drive?

Thanks.

Chuck(G)
June 14th, 2011, 03:23 PM
The DOB will read 1.2M and 1.44M floppies, but I've never had any success with it writing them--it always fails.

per
June 14th, 2011, 03:42 PM
The EOB uses the exact same chipset as the DOB, so the EOB will work just like a DOB if the lazer-hole emulating microcontroller is disabled by the toggle-switch on the rear of the card.

Shadow Lord
June 14th, 2011, 05:25 PM
@Chuck(G),

I've noticed the same thing with the DOB although only w/ 1.44MB disks I believe. I will have to check the 1.2MB disks (I am assuming you are talking about a non-protected vanilla floppy).

@per,

Just wondeirng do you have an EOB? If so, have you experienced the smae isues w/ trying to copy a 1.44MB disk (again non-protected).

So what about using the classic option board w/ a 1.2MB drive? Will it prevent the drive from working properly? Also does the logical format make any difference by that I mean how about MFD disks? Will the board be able to read these disks? I would assume so, after all it was designed to allow reading all sorts of weird sectors and hidden ones... If I ever get a chance I am going to do some serious methododical testing of the boards against different drives and disks.

Chuck(G)
June 14th, 2011, 07:03 PM
So what about using the classic option board w/ a 1.2MB drive? Will it prevent the drive from working properly? Also does the logical format make any difference by that I mean how about MFD disks? Will the board be able to read these disks? I would assume so, after all it was designed to allow reading all sorts of weird sectors and hidden ones... If I ever get a chance I am going to do some serious methododical testing of the boards against different drives and disks.

Same-oh, same-oh as 1.44M goes as far as data rate in high-density. Low density is 300KHz clock, but the DOB recognizes it.

My suspicion is that the DMA bandwidth isn't quite there for high-density floppies. I've even had the DOB hooked to an 8" floppy.

What I use it for mostly, is the capability of recognizing some common formats quickly and disclosing things like address marks, gap sizes, etc. If it doesn't know about a format, it's pretty worthless.

For actually copying things, I use a Catweasel.

Chuckster_in_Jax
June 14th, 2011, 07:44 PM
FWIW

http://retro.icequake.net/dob/

Shadow Lord
June 14th, 2011, 08:17 PM
FWIW

http://retro.icequake.net/dob/

I've read the info but it really doesn't deal with the questions I am asking. E.G. If I have the classic board will it interfere with the normal workings of a 1.2MB drive. However, as a resource it is great. Specially the pictures, which is the only place I have seen an EOB...

Chuck(G)
June 14th, 2011, 09:00 PM
When the board's not actually in use, it's a pass-through. So no, it won't interfere with normal operation.

Shadow Lord
June 14th, 2011, 09:09 PM
When the board's not actually in use, it's a pass-through. So no, it won't interfere with normal operation.

Thanks for all the info Chuck(G). That will be perfect as I intend to only use the board with the 360KB drive/disks. I've heard the Catweasel is an immensly powerful piece of HW but the SW is very limited so leveraging the power for a lay person (i.e. me) is very difficult.

Chuck(G)
June 15th, 2011, 08:53 AM
The Catweasel is a very simple-minded, yet powerful tool. One thing that's complicated the software picture is the move toward incorporating the logic into a Windows (or Linux) device driver. I still do most of my work with it in DOS, where you can get accurate and repeatable timings and not have to worry about context switches.

But then, I'm a dinosaur.

barythrin
June 15th, 2011, 09:18 AM
I haven't looked so I'm probably missing the obviously good results that may be out there but it seems like this would be quite a wonderful resource for the wiki here if someone with a any of these boards wants to put up tutorials on using them and what they can handle.

I've also been looking at getting one of these devices for years but never was sure what was a good choice nor does the budget really have room for a bad choice. At least I do see Catweasel's are still being made so the price is kinda easy to know what they should go for but mostly from Chuck suggesting it's complicated that made me worry.

Be pretty cool though to see examples and tutorials to gauge what one would be doing with X device and how to configure them, etc.

Chuck(G)
June 15th, 2011, 09:44 AM
Mostly, I use a Catweasl because I already have a couple. Almost all of the software I use is my own, so stuff that comes with the CW doesn't much matter.

If I had to do it today, I don't think I'd buy one, however. Microcontrollers are just too cheap. For $10, I can buy a 32-bit microcontroller with every type of interface I can think of integrated that coasts along executing one instruction per cycle at 80MHz. Other than providing a PCB to mount it on and a power supply, the rest is a matter of software (most have 5V tolerant inputs). So spending more than $100 on something where many of the hardware details are sketchy at best just isn't worth it for me.

One could take such a microcontroller and mount it on an ISA board and provide ADC, CAN, ethernet and USB interfaces, as well as SDHC storage and still have resources left over. Sort of like providing a Maserati to carry the mule that pulls your cart.

MikeS
June 15th, 2011, 09:48 AM
The DOB will read 1.2M and 1.44M floppies, but I've never had any success with it writing them--it always fails.What sort of 1.2M and 1.44M floppies would you run across that a normal PC FDC couldn't read (if we're talking about normal non-protected disks)?

And were there many seriously protected 1.2 & 1.4M disks?

Chuck(G)
June 15th, 2011, 12:07 PM
Believe it or not, I've run across a few--mostly grafts onto crufty old 8" industrial gear, but they do happen occasionally.