Re: Interest in Teac FD235J drives and FC-1 boards?

[Chuck Guzis via cctalk]

On 01/24/2018 02:35 PM, Glen Slick via cctalk wrote:
> On Wed, Jan 24, 2018 at 9:45 AM, Fred Cisin via cctalk
>  wrote:
>>
>> Does ImageDisk or Teledisk support it?
>> If so, then with the ED controller and one of these drives from Chuck, you
>> could image things such as the "4 Meg" floppies from NeXT. (4M is the
>> UNFORMATTED capacity of the 2.8M disk, and NeXT marketing thought that "4M"
>> sounded better than the "2.8M" formatted capacity)
>>
> 
> The ImageDisk 1.18 source code is available to inspect to answer the question.
> 
> If there is something special that software needs to do to select a
> 1000K bps data rate I don't see anything in the ImageDisk code which
> does that. What does software need to do to select the 1000K bps data
> rate for 2.8M mode?

Yes, the intel 82077 datasheet should tell you all you need.  One aspect
is that if you're operating in 1Mb/sec mode, you need to set
perpendicular mode in addition to setting the 1M data rate, so not
altogether straightforward.

--Chuck

Re: Interest in Teac FD235J drives and FC-1 boards?

[Glen Slick via cctalk]

On Wed, Jan 24, 2018 at 9:45 AM, Fred Cisin via cctalk
 wrote:
>
> Does ImageDisk or Teledisk support it?
> If so, then with the ED controller and one of these drives from Chuck, you
> could image things such as the "4 Meg" floppies from NeXT. (4M is the
> UNFORMATTED capacity of the 2.8M disk, and NeXT marketing thought that "4M"
> sounded better than the "2.8M" formatted capacity)
>

The ImageDisk 1.18 source code is available to inspect to answer the question.

If there is something special that software needs to do to select a
1000K bps data rate I don't see anything in the ImageDisk code which
does that. What does software need to do to select the 1000K bps data
rate for 2.8M mode?


http://www.classiccmp.org/dunfield/img/index.htm

imd.c:

unsigned Mtext[] = { // Translate Mode%3 to actual data rate
500, 300, 250 };

/*
 * Initialize data transfer mode (rate and density)
 * and update status display.
 */
void initmode(void)
{
unsigned x;
Mfm = (Mode / 3) ? 0x40 : 0x00;
out(FDC+5, x = Mode % 3);
w_gotoxy(3, 0, swin);
w_printf(swin, "%3uk %cD", Mtext[x], Mfm ? 'D' : 'S');
}

Re: Interest in Teac FD235J drives and FC-1 boards?

[Chuck Guzis via cctalk]

On 01/24/2018 09:45 AM, Fred Cisin via cctalk wrote:

> BTW, it is 2.8M.  It is NEVER 2.88M unless you REDEFINE "Megabyte" to be
> 1,024,000 bytes.  What moron does THAT?  (not the 1,000,000 used by
> marketing, nor the 1,048,576 used in computers (AKA MebiByte))

Well, 2.95MB or 2.81MiB.

That's why I don't use the "B" when I talk about these things.  The unit
used for 1.44M or 2.88M is a work of creative fiction.

But if you talk about "unformatted" capacity, which is perhaps a better
descriptive term for the medium and drive, nobody knows what you're
talking about.

We all make certain concessions.  So, a "360K" disk can easily hold 400K
and a 720K is twice the capacity of a 360K.  Obviously a 14400K must be
1.44M...and so on...

Used to be that numbers meant something.

--Chuck

Re: Interest in Teac FD235J drives and FC-1 boards?

[Fred Cisin via cctalk]

2.8M runs at 1,000,000 bits per second.
Such controllers exist, but are not very common.
Can Catweasel/kryoflux handle that data transfer rate?


On Wed, 24 Jan 2018, Jason T via cctalk wrote:

Looks like no on the KF:  https://forum.kryoflux.com/viewtopic.php?t=198
The post is from 2011, but as it's a hardware limitation and the KF is
still the same hardware as when it was released, I'd guess the answer
is still no.
As someone in that thread points out, there was no commercial (read:
"protected") software on 2.88 (is that really so?), so using a
"standard" controller, if you happen to have one, is fine.  In my
case, I think I have a 486-era IBM that supports the ED format.


Does ImageDisk or Teledisk support it?
If so, then with the ED controller and one of these drives from 
Chuck, you could image things such as the "4 Meg" floppies from NeXT. (4M 
is the UNFORMATTED capacity of the 2.8M disk, and NeXT marketing thought 
that "4M" sounded better than the "2.8M" formatted capacity)


BTW, it is 2.8M.  It is NEVER 2.88M unless you REDEFINE "Megabyte" to be 
1,024,000 bytes.  What moron does THAT?  (not the 1,000,000 used by 
marketing, nor the 1,048,576 used in computers (AKA MebiByte))

Re: Interest in Teac FD235J drives and FC-1 boards?

[Jason T via cctalk]

On Tue, Jan 23, 2018 at 10:14 PM, Fred Cisin via cctalk
 wrote:
> 2.8M runs at 1,000,000 bits per second.
> Such controllers exist, but are not very common.
> Can Catweasel/kryoflux handle that data transfer rate?

Looks like no on the KF:  https://forum.kryoflux.com/viewtopic.php?t=198

The post is from 2011, but as it's a hardware limitation and the KF is
still the same hardware as when it was released, I'd guess the answer
is still no.

As someone in that thread points out, there was no commercial (read:
"protected") software on 2.88 (is that really so?), so using a
"standard" controller, if you happen to have one, is fine.  In my
case, I think I have a 486-era IBM that supports the ED format.

Re: Interest in Teac FD235J drives and FC-1 boards?

[Christian Corti via cctalk]

On Wed, 24 Jan 2018, Bill Gunshannon wrote:

I wouldn't mind a couple of  FC-1 but I bet the price would be much more
than I can afford.


Speaking of the FC-1 boards: it appears that they support different sector 
sizes, as well as MFM and FM encoding. How do you program this?


Christian

Re: Interest in Teac FD235J drives and FC-1 boards?

[Bill Gunshannon via cctalk]

I wouldn't mind a couple of  FC-1 but I bet the price would be much more
than I can afford.

bill


From: cctalk <cctalk-boun...@classiccmp.org> on behalf of Chuck Guzis via 
cctalk <cctalk@classiccmp.org>
Sent: Wednesday, January 24, 2018 2:00 AM
To: Fred Cisin via cctalk
Subject: Re: Interest in Teac FD235J drives and FC-1 boards?

On 01/23/2018 09:27 PM, Fred Cisin via cctalk wrote:

> Being part of the problem, . . . I was very happy in 1991, to finally
> find Windoze 3.0 and 3.1 on CD-ROM, to stop juggling several dozen
> installation floppies.

The last-gasp installation floppies--Microsoft 21-sector DMF
distribution (or IBM bizarre XDF 8192+2048+1024+512) floppies for OS/2).
 In the end, I don't think 2.88M distribution would have helped.
Software was growing too fast.

I did encounter people saying that they had great results using HD media
as ED in some host-sense IBM drives.   I told them to check back with me
in a couple of years as to the readability of those disks.

I've still got one of the 20MB Brier floppy drives, though heaven knows
why...

It's funny--I routinely get HD 5.25" disks written on old DD CP/M
machines that read just fine, by and large.  And lots of WP 3.5"
floppies (240K FM) written on HD media and never had run across one that
couldn't be read.

But ED on HD media seems like more of a hope than reality to me.

--Chuck

Re: Interest in Teac FD235J drives and FC-1 boards?

[Chuck Guzis via cctalk]

On 01/23/2018 09:27 PM, Fred Cisin via cctalk wrote:

> Being part of the problem, . . . I was very happy in 1991, to finally
> find Windoze 3.0 and 3.1 on CD-ROM, to stop juggling several dozen
> installation floppies.

The last-gasp installation floppies--Microsoft 21-sector DMF
distribution (or IBM bizarre XDF 8192+2048+1024+512) floppies for OS/2).
 In the end, I don't think 2.88M distribution would have helped.
Software was growing too fast.

I did encounter people saying that they had great results using HD media
as ED in some host-sense IBM drives.   I told them to check back with me
in a couple of years as to the readability of those disks.

I've still got one of the 20MB Brier floppy drives, though heaven knows
why...

It's funny--I routinely get HD 5.25" disks written on old DD CP/M
machines that read just fine, by and large.  And lots of WP 3.5"
floppies (240K FM) written on HD media and never had run across one that
couldn't be read.

But ED on HD media seems like more of a hope than reality to me.

--Chuck

Re: Interest in Teac FD235J drives and FC-1 boards?

[Fred Cisin via cctalk]

On Tue, 23 Jan 2018, Chuck Guzis via cctalk wrote:

The Compaticard IV and a few other ISA cards support ED mode also.
But again, why?  I still have a box of the Imation ED floppies (barium
ferrite).  The price was ridiculous for floppies of the time.


Until CD-rOM became the standard for software distribution, doubling the 
capacity per floppy was always good news.  And there was always the hopee 
that media price would come down "once they catch on".


2.8M seemed far more likely to catch on than "Floptical" (20MB)
I was often wrong about such things; I thought that surely Microsoft would 
fix SMARTDRV before releasing Windoze 3.10, but that didn't happen until 
DOS 6.20




Being part of the problem, . . . 
I was very happy in 1991, to finally find Windoze 3.0 and 3.1 on 
CD-ROM, to stop juggling several dozen installation floppies.

Re: Interest in Teac FD235J drives and FC-1 boards?

[Chuck Guzis via cctalk]

On 01/23/2018 08:45 PM, Fred Cisin via cctalk wrote:

> They almost started to catch on, particularly in some PS/2.
> I had one with a MicroSolutions "Backpack" parallel port interface.

It would be a simple matter to upgrade a 1.44M backpack floppy with a
2.88M capable drive, as the controller is a PC8477 and the driver
software still supports it (as of the last units to roll off the line).

The Compaticard IV and a few other ISA cards support ED mode also.

But again, why?  I still have a box of the Imation ED floppies (barium
ferrite).  The price was ridiculous for floppies of the time.

> For the sake of "completeness", and maybe for NeXT disks, they would be
> essential.
> 
> And it is a versatile drive for 1.4M
> 
>

Re: Interest in Teac FD235J drives and FC-1 boards?

[Fred Cisin via cctalk]

2.8M runs at 1,000,000 bits per second.
Such controllers exist, but are not very common.


On Tue, 23 Jan 2018, Chuck Guzis via cctalk wrote:

Fred.  They've been fairly common since the 496 days (I've got several
machines with the controllers on them, including a 486 VLB system).


They almost started to catch on, particularly in some PS/2.
I had one with a MicroSolutions "Backpack" parallel port interface.


They kind of died out during the P2-P3 days and I don't know if I've got
a P4 system with that capability.
Of course, the media is darned near unobtainium, so the question is
somewhat moot.
But the drives themselves usually have more configurability than the
usual FD235HF drives.


For the sake of "completeness", and maybe for NeXT disks, they would be
essential.

And it is a versatile drive for 1.4M

Re: Interest in Teac FD235J drives and FC-1 boards?

[Chuck Guzis via cctalk]

On 01/23/2018 08:14 PM, Fred Cisin via cctalk wrote:

> Be aware that you will also need a different controller, or some minor
> modifications.
> 
> PC controllers normally support 250,000 bits per second ("360K", "720K"),
> and 500,000 bits per second ("1.2M, "1.4M")
> SOMETIMES 125,000 bits per second for 5.25" SD/FM.
> 
> 2.8M runs at 1,000,000 bits per second.
> 
> Such controllers exist, but are not very common.


Fred.  They've been fairly common since the 496 days (I've got several
machines with the controllers on them, including a 486 VLB system).

They kind of died out during the P2-P3 days and I don't know if I've got
a P4 system with that capability.

Of course, the media is darned near unobtainium, so the question is
somewhat moot.

But the drives themselves usually have more configurability than the
usual FD235HF drives.

--Chuck

Re: Interest in Teac FD235J drives and FC-1 boards?

[Fred Cisin via cctalk]

On Tue, Jan 23, 2018 at 6:36 PM, Chuck Guzis via cctalk
 wrote:

I've got a fellow with a stock of Teac FD235J (2.88) drives and about a
dozen bare Teac FC-1 SCSI boards.

On Tue, 23 Jan 2018, Jason T via cctalk wrote:

I'm interested, if the drives can be used for imaging 2.88 media (a la
IBM, etc).  Probably not so much the SCSI boards - the drives seem to
have regular 34-pin interfaces, if I'm looking at the right photos.


Be aware that you will also need a different controller, or some minor 
modifications.


PC controllers normally support 250,000 bits per second ("360K", "720K"),
and 500,000 bits per second ("1.2M, "1.4M")
SOMETIMES 125,000 bits per second for 5.25" SD/FM.

2.8M runs at 1,000,000 bits per second.

Such controllers exist, but are not very common.


Can Catweasel/kryoflux handle that data transfer rate?

Re: Interest in Teac FD235J drives and FC-1 boards?

[Jason T via cctalk]

On Tue, Jan 23, 2018 at 6:36 PM, Chuck Guzis via cctalk
 wrote:
> I've got a fellow with a stock of Teac FD235J (2.88) drives and about a
> dozen bare Teac FC-1 SCSI boards.

I'm interested, if the drives can be used for imaging 2.88 media (a la
IBM, etc).  Probably not so much the SCSI boards - the drives seem to
have regular 34-pin interfaces, if I'm looking at the right photos.

Interest in Teac FD235J drives and FC-1 boards?

[Chuck Guzis via cctalk]

I've got a fellow with a stock of Teac FD235J (2.88) drives and about a
dozen bare Teac FC-1 SCSI boards.

I'm trying to gauge interest--I don't think he wants to sell them
onesy-twosy, but I'm willing to act as intermediary for single-unit
purchases if there is sufficient interest.

--Chuck