English Amiga Board


Go Back   English Amiga Board > Support > support.Hardware > Hardware mods

 
 
Thread Tools
Old 14 September 2012, 16:17   #241
alenppc
Registered User
 
Join Date: Apr 2012
Location: Canada
Age: 41
Posts: 836
Here's an update. Bought a bunch of brand new DSDD disks on Ebay, unformatted. They format wonderfully with original Amiga drives, modded Chinon PC drives and the like. The Samsung drives still refuse to format them. Not only that, they won't format them even when connected to a PC without any mods.

Conclusion: these drives are pure garbage. I am amazed that Samsung was allowed to sell this crap! They are essentially floppy-readers only, they can't write. Amazing. So yeah, I wasted money on them but it was a valuable lesson learned... stay away from Samsung.
alenppc is offline  
Old 14 September 2012, 16:30   #242
r.cade
Registered User
r.cade's Avatar
 
Join Date: Aug 2006
Location: Augusta, Georgia, USA
Posts: 421
Send a message via AIM to r.cade Send a message via MSN to r.cade Send a message via Yahoo to r.cade
Some HD drives won't write to DD disks, you found one.

It probably does not have the HD/SD detect circuitry anymore, to save some pennies. It's not like it's needed in modern times, except for using extinct media.

They stopped making cars that will accept "regular" (non-unleaded) gas anymore, also.

Last edited by r.cade; 14 September 2012 at 16:41.
r.cade is offline  
Old 14 September 2012, 23:22   #243
prowler
Global Moderator

prowler's Avatar
 
Join Date: Aug 2008
Location: Sidcup, England
Posts: 10,300
Quote:
Originally Posted by alenppc View Post
Here's an update. Bought a bunch of brand new DSDD disks on Ebay, unformatted. They format wonderfully with original Amiga drives, modded Chinon PC drives and the like. The Samsung drives still refuse to format them. Not only that, they won't format them even when connected to a PC without any mods.

Conclusion: these drives are pure garbage. I am amazed that Samsung was allowed to sell this crap! They are essentially floppy-readers only, they can't write. Amazing. So yeah, I wasted money on them but it was a valuable lesson learned... stay away from Samsung.
But... but my KryoFlux was supplied complete with a Samsung SFD-321B/EF floppy drive!
prowler is offline  
Old 17 September 2012, 17:44   #244
alenppc
Registered User
 
Join Date: Apr 2012
Location: Canada
Age: 41
Posts: 836
@r.cade
This is the first time I hear of this. I don't think the analogy is correct, this is as idiotic as making blu-ray 2.0 drives that refuse to read 1.1 discs... Is there a way to add this circuit back somehow?

@prowler
It's possible that this wonderful "feature" is not present on your revision, as on my (TA) revision. I suppose one could still use these drives for reading floppies and use an external drive for writing them. Gotta try formatting an HD floppy on the PC with this fantastic drive, to see whether it makes a difference.
alenppc is offline  
Old 31 October 2012, 22:33   #245
Arnie
R.I.P Smudge 18-08-16

Arnie's Avatar
 
Join Date: Aug 2005
Location: Leicester/UK
Age: 63
Posts: 3,966
I thought i would share this with you. I have just modified a Panasonic JU-256A428P following the instructions from post #226 by dJOS.
Arnie is offline  
Old 31 October 2012, 23:12   #246
lesta_smsc
Registered User

lesta_smsc's Avatar
 
Join Date: Feb 2012
Location: United Kingdom
Posts: 2,731
Would be useful if these 'guides' could be collated into a Downloads area as .pdf or similar
lesta_smsc is offline  
Old 31 October 2012, 23:29   #247
dJOS
Registered User

dJOS's Avatar
 
Join Date: Aug 2012
Location: Melbourne, Australia
Posts: 888
Quote:
Originally Posted by Arnie View Post
I thought i would share this with you. I have just modified a Panasonic JU-256A428P following the instructions from post #226 by dJOS.
Cool, but kipper2k did the hard work figuring out the original mod so I can't take any credit.

dJOS is offline  
Old 01 November 2012, 19:53   #248
Arnie
R.I.P Smudge 18-08-16

Arnie's Avatar
 
Join Date: Aug 2005
Location: Leicester/UK
Age: 63
Posts: 3,966
Quote:
Originally Posted by dJOS View Post
Cool, but kipper2k did the hard work figuring out the original mod so I can't take any credit.
Ah OK but, if you hadn't shown a pic with pins 1&2 bridged then I would have followed kippers pic and bridged pins 1&3, so I personally thank both Kipper and you....Thanks
Arnie is offline  
Old 01 November 2012, 23:26   #249
dJOS
Registered User

dJOS's Avatar
 
Join Date: Aug 2012
Location: Melbourne, Australia
Posts: 888
Quote:
Originally Posted by Arnie View Post
Ah OK but, if you hadn't shown a pic with pins 1&2 bridged then I would have followed kippers pic and bridged pins 1&3, so I personally thank both Kipper and you....Thanks
The irony is cant remember why I bridged 1 & 2 instead of 1 & 3!
dJOS is offline  
Old 13 December 2012, 12:42   #250
Mrs Beanbag
Glastonbridge Software
Mrs Beanbag's Avatar
 
Join Date: Jan 2012
Location: Edinburgh/Scotland
Posts: 2,202
Was looking at an Alps DF354H on ebay yesterday, seems quite an easy one to mod and maybe an instructive project. But I'm still intrigued as to why it's so difficult to get a drive to work properly as HD, however when I look at the pinouts I'm now puzzled as to how it ever works at all, because we need pin 2 (density select) rewired to the Disk Change signal... so where is our density select signal supposed to go?
Mrs Beanbag is offline  
Old 13 December 2012, 12:49   #251
demolition
Unregistered User
demolition's Avatar
 
Join Date: Sep 2012
Location: Copenhagen / DK
Age: 40
Posts: 4,146
The main reason that you cannot modify a PC drive into reading DSHD disks in Amigaformat is that it requires you to slow the RPM of the drive to 150 RPM instead of the default 300 RPM, which is not trivial. PC uses 300 RPM for both DD and HD formats.
demolition is offline  
Old 13 December 2012, 13:50   #252
Mrs Beanbag
Glastonbridge Software
Mrs Beanbag's Avatar
 
Join Date: Jan 2012
Location: Edinburgh/Scotland
Posts: 2,202
How about reading PC HD disks on Amiga? Also how does the Amiga know there is a HD disk in the drive?
Mrs Beanbag is offline  
Old 13 December 2012, 16:10   #253
robinsonb5
Registered User
 
Join Date: Mar 2012
Location: Norfolk, UK
Posts: 982
Quote:
Originally Posted by Mrs Beanbag View Post
How about reading PC HD disks on Amiga?
Same thing - on the PC, HD disks deliver the datastream at twice the rate of DD disks. Paula can't cope with that, so Amiga HD drives halve the motor speed for HD disks, so the data rate remains the same.
robinsonb5 is offline  
Old 13 December 2012, 16:43   #254
Mrs Beanbag
Glastonbridge Software
Mrs Beanbag's Avatar
 
Join Date: Jan 2012
Location: Edinburgh/Scotland
Posts: 2,202
hm, I wonder if it's possible to mod Paula, then, instead.
Mrs Beanbag is offline  
Old 13 December 2012, 18:59   #255
robinsonb5
Registered User
 
Join Date: Mar 2012
Location: Norfolk, UK
Posts: 982
Quote:
Originally Posted by Mrs Beanbag View Post
hm, I wonder if it's possible to mod Paula, then, instead.
I doubt it - the limitation is very much intrinsic to the Amiga's design: in order to shift twice as much data, Paula would need twice as many DMA slots, and would need to use a faster clock for disk transfers. (If Commodore had updated Paula to make use of the 64-bit fetch modes that allow the AGA screenmodes, then it'd be possible - sadly, they didn't.)

But I digress - the Alps drive is a fairly easy one to modify - I've done a few of those myself. Just need a steady hand, good light and either very good eyesight or a magnifying glass.

Last edited by robinsonb5; 13 December 2012 at 19:17.
robinsonb5 is offline  
Old 13 December 2012, 19:39   #256
Mrs Beanbag
Glastonbridge Software
Mrs Beanbag's Avatar
 
Join Date: Jan 2012
Location: Edinburgh/Scotland
Posts: 2,202
Quote:
Originally Posted by robinsonb5 View Post
I doubt it - the limitation is very much intrinsic to the Amiga's design: in order to shift twice as much data, Paula would need twice as many DMA slots, and would need to use a faster clock for disk transfers. (If Commodore had updated Paula to make use of the 64-bit fetch modes that allow the AGA screenmodes, then it'd be possible - sadly, they didn't.)
Maybe we could buffer it somehow, read the data into a buffer and output it at half speed. The disk would do two complete revolutions, but the actual read would only happen on the first revolution... maybe...

Quote:
But I digress - the Alps drive is a fairly easy one to modify - I've done a few of those myself. Just need a steady hand, good light and either very good eyesight or a magnifying glass.
It looked it, in fact most of the mods could be done off the drive, just on the cable. The only one that actually needs soldering is the ready signal, and optionally the HD detect if you can't be bothered putting tape on your HD disks. Unless I'm missing something?

Considering getting one with a black bezel and modding my case to let it poke through... I stripped the screw holes at the front last time I put it back together anyway
Mrs Beanbag is offline  
Old 13 December 2012, 21:29   #257
robinsonb5
Registered User
 
Join Date: Mar 2012
Location: Norfolk, UK
Posts: 982
Quote:
Originally Posted by Mrs Beanbag View Post
Maybe we could buffer it somehow, read the data into a buffer and output it at half speed. The disk would do two complete revolutions, but the actual read would only happen on the first revolution... maybe...
I think that's how Power Computing's external HD drive worked. (Kind of like the opposite of a scandoubler!)

Quote:
It looked it, in fact most of the mods could be done off the drive, just on the cable. The only one that actually needs soldering is the ready signal, and optionally the HD detect if you can't be bothered putting tape on your HD disks. Unless I'm missing something?
You're probably right - but to be honest I found the idea of soldering onto the drive's circuit board less daunting (and certainly more fun!) than counting strands of ribbon cable, separating, cross-connecting and suchlike!

Quote:
Considering getting one with a black bezel and modding my case to let it poke through... I stripped the screw holes at the front last time I put it back together anyway
That's a possibility, but if you want a less drastic intervention, what I did was remove the fascia and button from the drive, then shaped a new button out of polymorph, and Araldited it on.

Pretty? No. Serviceable? Yes. (That's a long-standing crack in the casework, BTW! )
Attached Thumbnails
Click image for larger version

Name:	EjectButton.jpg
Views:	484
Size:	59.5 KB
ID:	33437  
robinsonb5 is offline  
Old 22 December 2012, 15:38   #258
Retroplay
Lemon Curry ?

Retroplay's Avatar
 
Join Date: Sep 2004
Location: Denmark
Age: 46
Posts: 3,677
I bought two new floppy drives from AmigaKit and I have some problems getting one of the drives to work properly.

One of them keeps giving me "DF0:????" on every disk I insert.
Disks that I know work and are perfectly fine on my other 1200 with original drive.

The other drive seems to work fine, although the demo "World of Commodore" gave me an error while loading (black screen with yellow text in bottom left corner), track load problems perhaps ?

Does anybody have any suggestions before I raise a support ticket at AmigaKit ?
Retroplay is offline  
Old 22 December 2012, 16:01   #259
duga
Registered User
 
Join Date: Nov 2010
Location: Sweden
Posts: 488
Quote:
Originally Posted by Retroplay View Post
I bought two new floppy drives from AmigaKit and I have some problems getting one of the drives to work properly.

One of them keeps giving me "DF0:????" on every disk I insert.
Disks that I know work and are perfectly fine on my other 1200 with original drive.

The other drive seems to work fine, although the demo "World of Commodore" gave me an error while loading (black screen with yellow text in bottom left corner), track load problems perhaps ?

Does anybody have any suggestions before I raise a support ticket at AmigaKit ?
Turn the cable connector 180 degrees at the floppy drive and see if that helps.
duga is offline  
Old 22 December 2012, 16:01   #260
robinsonb5
Registered User
 
Join Date: Mar 2012
Location: Norfolk, UK
Posts: 982
Quote:
Originally Posted by Retroplay View Post
One of them keeps giving me "DF0:????" on every disk I insert.
Disks that I know work and are perfectly fine on my other 1200 with original drive.
What happens if you try and format a blank disk in this drive?
robinsonb5 is offline  
 


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Similar Threads
Thread Thread Starter Forum Replies Last Post
Copying Amiga disks using Floppy drives on a PC. hamster support.Hardware 22 01 September 2020 10:46
Amiga 5.25-inch floppy disks and drives mips support.Hardware 24 03 May 2013 20:40
List of Amiga compatible PC floppy drives Olecranon support.Hardware 12 05 October 2011 17:38
Amiga floppy drives cinemawareman Amiga scene 5 17 March 2011 15:40
replacing amiga floppy drives with hard drives Gordon support.Hardware 2 06 March 2007 00:44

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +2. The time now is 22:03.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
Page generated in 0.12556 seconds with 14 queries