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Posted By

Porosz
on 2018-04-04
21:37:27
 1541 double stack mod -

So, has anyone tried to tie two 1541 floppy drives together, with one board? Could it be done? Basic 3.5 suggests the disk drive should be one unit, with two devices.

Posted By

gerliczer
on 2018-04-05
02:20:59
 Re: 1541 double stack mod -

Probably not. No. That's a misinterpretation.

However, there were double drives manufactured by Commodore (with IEEE-488 interface) and and by third parties (in the USA).

Posted By

MMS
on 2018-04-05
19:03:31
 Re: 1541 double stack mod -

I agree with gerliczer, this command try to refer to the dual floppy disc drives, command directly taken from BASIC 4.0 (PET models).

Unfortunately I know only one single drive with IEC connection that may fit to this category (could ever be connected to Plus/4 or C16), it was the MSD SD-2 dual drive (this one had both IEEE-488 and IEC port too). But this is a US based 110V device.

There were some old IEEE-488 based huge beasts made by Commodore itself, like the LP8250 (the singe drive slim version was SFD-1001) with two units in one house, 1MB disc capacity, double sided discs, or the CBM4040, CBM8050, etc
Unfortunately for a really long time there was no way to connect them to the 264 series, and still today this connection is rather limited in speed.

This one worths a read about the C= drives ever made:
http://www.floodgap.com/retrobits/ckb/secret/periph.html

Too bad that for Plus/4 no IEEE-488 cartridge developed by Commodore (as the VIC-1112 for VC-20 or IEE-488 cartridge for C64) and no other maker did it, like for C64 the CMD ; Interpod on IEC (slow), Quicksilver 128 or Buscard II

There is one working and cheap solution (I have one working one) called IEC2IEE interface, based on Jochen Adler design at http://www.nlq.de/

You can directly connect an IEEE-488 dual disc drive to this interface, and fully command it with BASIC commands. But really, really slow, like an 1541, and no fastloader exists.
It is told to support JiffyDOS, but I do not have that ROM to test. IEEE-488 drives are typically 4-5x faster than the IEC drives, but with this interface it is not recogkizable, as IEC bus defines the maximum speed.

This is my setup (still with C64):
forum/31037

In case you are really interested in IEEE-488 inteface for Commodore computers:
http://sleepingelephant.com/denial/wiki/index.php?title=VIC-1112_IEEE-488_interface_cartridge
http://www.nightfallcrew.com/19/08/2012/commodore-64-ieee-488-cartridge/

With IEEE-488 you can even connect a hard disc drive to the 8 bit Commodores, I suppose it would work :
http://members.optusnet.com.au/spacetaxi64/HD-HISTORY/C64HD-HISTORY.html

Posted By

Ken
on 2018-04-05
21:06:16
 Re: 1541 double stack mod -

I have toyed with the idea of something close to that
I have been very slowly developing a direct drop in board for the sx-64 to make it a dual drive
and I have toyed with the idea of making the board so we can have a drive like the msd-sd2 but 100% compatible
but that to is on my huge mound of (to do) projects

Posted By

Porosz
on 2018-04-12
00:26:27
 Re: 1541 double stack mod -

I looked at some of the pictures, and noticed the 1572 side by side model.... I know the 1571 drives were problematic and complicated, well, now I know.
Still, piling two mechanical parts with one board sounds like a trick someone was thinking of, when maybe all you have to do is split the serial cord, with a Y adapter, and then the device will be on the same cord 0 and 1 . Think that would work?
Other thoughts are, I never had it plugged in parallel ; so if that has it easier....

Posted By

MMS
on 2018-04-12
14:31:07
 Re: 1541 double stack mod -

I am not an expert, but I think Y cable does not help here.

These drives are so-called intelligent drives with their own CPU and memory, kernel, executing commands, in fact running programs internally.
Because of that, each device will listen to the IEC, and will follow only those commands addressed to them.
If you do not have a kernel clearly defines for the device it has two mechanisms, and one of them is 8,0., the other is 8,1, then the Y cable just create device 8 and 9 or two #8 devices, that will not work together.

I know it, as initially the IEC2IEE has it's own preset #9. I connected my 1571 with daisy chain, and nothing worked. It took 5-10 minutes to realize I forgot that I set the DIP switches on my 1571 to #9, because my main drive was 1541/II #8.
In fact, till today I did not notice the huge incompatibility of 1571 with 1541 stuff. (I have to admit the latest games with trackloaders not transferred yet (I have no SD card based device yet to transfer stuff from PC) )

Posted By

Jakec
on 2018-04-13
02:22:16
 Re: 1541 double stack mod -

Then do you want to copy one drive from another drive?
Because it works, for example 1541 to 1551 etc... .



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