! ! 3 1/2" PC Drive/s on a beeb ! !

[danielj]

PSU-wise, something like this is ideal:

http://www.ebay.co.uk/itm/320705061184

Thx for posting that link.. might find a few uses for one of those.... gotta be worth a fiver with free delivery. even if only for bench testing purposes.

They go bang with more frequency than Beebmaster's LV ROM Drives! Stay well clear of those china cheapie PSUs. They also run VERY hot, when they do run at all!

It's true

It's super-toasty. Do you have an alternative recommended item?

d.

[textbook]

Thanks for the warning guys.. unfortunately I didn't read it until now.. ie. after I throwed away a fiver ordering it. It arrived today.. better stand well back when I plug it in..

[daveejhitchins]

Love the new shirt

Unfortunately my compact's PSU died and next time I looked the whole kit had beed trashed - early '90s

Must add, before Mrs. H's time.

Dave H

[mark.treleaven]

I have a Alps Electric Co., Ltd 1.44MB 3.5" Drive DF354H090F, I have hooked it up to my BBC Master 128, and it works ok.

But when I write images out from OmniFlop to 720k DD floppy discs and try them in the BBC Master I get errors like Bad Directory or Bad Program etc.

do I need to set the stepping speed of my drive with a *FX command?
I have tried getting specs of this drive online to see what its native stepping speed it, but no luck

Thanks in advance
Mark

[danielj]

Wouldn't have thought it'd be stepping speed. With omniflop make sure you format the disc to the relevant format first before writing it out, see if that helps.

It could, of course, be that the floppy drive controller on your PC doesn't get on with omniflop...

d.

[mark.treleaven]

I usually use the format-write (initilise disk) option
My Master is set to FDrive 3, and as far as I can tell that is a step of 30ms and settle of 30ms.
Seems to be perfectly ok with my side-by-side Cumana 5.25 drives.

Will try format, then write and will try the slow step option as well, see if i get better results.

If not I should have the UPURS ROM by Friday, so will eliminate the need for OmniFlop

[flaxcottage]

This is sounding like incompatibility between 3.5" floppy drives.

At a guess I would say that you are using Omniflop on a different floppy drive than the one on your Beeb. I had this problem and it is most frustrating. Changing the drive motor stepping had no effect for me.

Try using the same drive for both Omniflop and with the Master 128. That way you remove a variable from the equation.

Omniflop is also sensitive to drive type. Some drives will just not work; some read but not write and some appear to do both but the written disk will not read in the destination computer.

The drive you mention is a 1.44Mb, HD drive. These do not seem to work very well on the Master 128, especially the 'modern' ones. You need a 720K DD drive for best results or failing that one of the first HD floppy drives.

Another thing that might work is cleaning the drive heads using a proprietary 3.5" disc drive cleaner. These are easily and cheaply available from eBay.

It is worth persisting with 3.5" drives, though, as they are a lot quieter, faster and seem to last longer.

- John

[mark.treleaven]

Thanks for your insights John
You are correct the drive I am using to write the discs is different from the one I am using to read.
Its a work computer so cant really be swapping out the drives, knowing my luck the boss will walk in as I have it all apart and cables hanging out everywhere.

But as you say, I will persist.

[mark.treleaven]

I have got a 3.5 inch drive working on my BBC Master fine.

Does anyone know where I can get an enclosure for the drive, at the moment its just a bare drive with cables out the back of it.

Would be nice to encase it and tidy it up a bit.

[flaxcottage]

3.5" enclosures are as common as hen's teeth I have found. An idea might be to use a 5.25" single drive case with a 5.25" to 3.5" adapter. That is not cheap, though, as you will have to buy the 5.25" drive first.

I have seen someone who made a wooden case - not bad if you like stained plywood.

How are your metalworking skills? Aluminium sheet is cheap, relatively, and once sprayed will look quite good.

If you do find a source of cases, please let us know as I could do with a few myself.

- John

[danielj]

There's a thing - mine sit bare, must be said. Probably an amiga external drive case, or something equivalent is the best bet. Someone on here may well have an old enclosure too.

Alternatively you could get a project case of appropriate size and attack it with a dremel? IIRC someone was selling dual drives that were in an enclosure that had been put together like that? I think someone posted about it on here too..

d.

[mark.treleaven]

I did see the double stacked floppy drives for sale.

Also did get a plastic enclosure from my local Maplin, but even though its internal dimensions were said to be 100mm they were actually about 97mm so my drive didnt fit

So will see what i can find out

[sydney]

There's a thing - mine sit bare, must be said. Probably an amiga external drive case, or something equivalent is the best bet. Someone on here may well have an old enclosure too.

Alternatively you could get a project case of appropriate size and attack it with a dremel? IIRC someone was selling dual drives that were in an enclosure that had been put together like that? I think someone posted about it on here too..

d.

Be careful with amiga external drives. I bought two with broken drives earlier this year to use the cases but the drives were slimline ones and the cases were too small for a standard drive. I might have a go at repairing the drives sometime though as one probably just needs a belt replacing.

[SimonSideburns]

Great thread and lots of useful information, even it most of the technical stuff was way over my head.

While reading, a thought entered into my head:

What about the possibility of plugging in and using a 1.44mb HD USB floppy drive into Retro Clinic's Data Centre and using that?

I know it wouldn't be standard but at least you could access the files on the drive.

What problems may be envisaged?

Simon

[duikkie]

can we not clear up this item a bit

put all the important stuff first
and then what you can do ( the beeb twist)
what the errors are if you are stubborn.

make an other item that is not sticky
explaining it

[richardtoohey]

What about the possibility of plugging in and using a 1.44mb HD USB floppy drive into Retro Clinic's Data Centre and using that?

Wouldn't you have to have a driver for that, though? Something to pull/push the data over USB?

[poink]

What about the possibility of plugging in and using a 1.44mb HD USB floppy drive into Retro Clinic's Data Centre and using that?

Wouldn't you have to have a driver for that, though? Something to pull/push the data over USB?

I think floppy drives tend to turn up on USB buses as USB mass storage devices (with a handful of extensions if you'd like to do something like format one) so the DataCentre should already support them.

The downside of this is that USB floppy drives only support a handful of built in formats:

For DD disks: 720KB (80 tracks, 2 heads, 9 sectors/track, 512 byte sectors)
HD disks: 1.25MB (77 tracks, 2 heads, 8 sectors/track, 1024 byte sectors) and 1.44MB (88 tracks, 2 heads, 18 sectors/track, 512byte sectors)

These are identified by a single format type byte, so it looks like there's no 'uploading a format description and reading an ADFS floppy'.

[irobot]

Hello all, I have a 3.5 in disk drive working with DD disks (formatted on 1770 DFS late Beeb but mine has DFS 0.9 which has no formaton the DFS. I need to obtain the form 40 software on a 3.5 in . I saw a previous posting also needing this and wonder if any one can help. cheers , Steve

[sydney]

JGH has a quick formatting type in on mdfs.net here

Code: Select all

REM > FormDFS
REM Quick Formatter
DIM X% 31,data% 511:Y%=X%DIV256:*DISK
ON ERROR REPORT:PRINT " at line ";ERL:OSCLI"FX180,"+STR$(PAGE/256):END
*FX180,64
INPUT"Drive:  "drive%
INPUT"Tracks: "num%
FOR track%=0 TO num%-1
  PRINT CHR$13;"Track ";track%;
  FOR sector%=0 TO 9
    data%!(sector%*4)=track%
    data%?(sector%*4+2)=(sector%+track%*7)MOD10
    data%?(sector%*4+3)=1
  NEXT sector%
  X%?0=drive%
  X%!1=data%
  X%!5=&6305
  X%?7=track%
  X%!8=&10002A10
  A%=127:REPEAT:CALL&FFF1:UNTIL X%?12<>&10
  IF X%?12:PRINT" error &";~X%?12
NEXT track%:PRINT
FOR A%=0 TO 511 STEP 4:data%!A%=0:NEXT A%
data%?&107=num%*10
data%?&106=num%/25.6
X%?0=drive%
X%!1=data%
X%!5=&4B03
X%!9=&22
A%=127:REPEAT:CALL&FFF1:UNTIL X%?10<>&10
IF X%?10:PRINT"write error &";~X%?10
OSCLI"FX180,"+STR$(PAGE/256):END

[irobot]

Hello Sydney, I shall try that formating routine . Its a great improvement having 3.5in floppies as those 5in ones are so unreliable.
cheers, Steve

[paulv]

I suspect you'll need DFS 1.21 for the 3.5" floppies to work fully on your machine as there are compatibility issues between the 8271 disc controller and 3.5" floppies.

DFS 1.21 is an unofficial hack to make 3.5" discs work correctly.

Otherwise, get yourself a 1770 controller from Mark H. (RetroClinic) and then you'll have a trouble free experience and format commands in ROM to boot

Paul

[jonb]

I'm a bit late to the party, but my 3.5" drives (DSDD) work perfectly on both my beebs and the Electron. What's the problem?

[jgharston]

I'm a bit late to the party, but my 3.5" drives (DSDD) work perfectly on both my beebs and the Electron. What's the problem?

Some drives (at a guess about 50% of them) implement the disk ready response with slightly different timing to what the 8271 DFS expect, so the DFS times out. DFS 1.21 fixes this by retrying any time the drive returns Not Ready. 1770 DFS has no problems with 3.5" drives, and some 3.5" drives have no problem with 8271 DFS, and some problematic drives can be hardware patched.

Sprow has written up the issue on his site.

[BeebMaster]

PSU-wise, something like this is ideal:

http://www.ebay.co.uk/itm/320705061184

Thx for posting that link.. might find a few uses for one of those.... gotta be worth a fiver with free delivery. :) even if only for bench testing purposes.

[-X They go bang with more frequency than Beebmaster's LV ROM Drives! Stay well clear of those china cheapie PSUs. They also run VERY hot, when they do run at all!

I only just saw this, and that item is still available. It's something I could really make use of, I've never seen a mains PSU ending in a hard drive connector like that before. I'd probably have bought a couple of dozen of them if it wasn't for this warning. Anybody know of a reliable substitute?

[CMcDougall]

^5v 1amp (some 2amp) USB adaptors for mobile phones /tablets /cameras /etc:

and for the 12v, use a broadband hub box adaptor, they range from 1amp to 2.5
but need two mains plug sockets, not one

[poink]

^5v 1amp (some 2amp) USB adaptors for mobile phones /tablets /cameras /etc:

Yup, they're really useful.

Do be careful that you're buying 'good' ones, unbranded cheapy phone adaptors can be as bad as the one with the hard disk Mate-n-Lok style. (And by 'bad', I mean shock and fire hazards; a search for something like 'cheap charger danger' will find you loads of news stories.)

Incidentally, I have one of the HD ones. It's /very/ light. I fear that there might not be much in the way of components for things like safety.

and for the 12v, use a broadband hub box adaptor, they range from 1amp to 2.5
but need two mains plug sockets, not one

Modern 90mm floppy drives may actually only need 5V, so one of those USB adaptors might well be all you need.

It's also fairly easy to get 5V from 12V. If you don't need much current, then you can easily build a linear regulator (couple of capacitors and an 7805). If you need more, or you want an easy route, it looks like there's a fair few 5V switchmode DC-DC supplies on eBay which would easily do the trick (note, I've not tested these personally, so I'm going by spec).

[martinjharvey]

I've just added a 3.5 Samsung SFD-321B floppy to my BBC Master and got it working pretty much straight off I've been using some old Amiga disks and can format and do everything else you would expect. However, I could do with advice on a few issues:

1: LED on 3.5 floppy is always lit whether a disk is in or the drive is active. The motor doesn't sound to be active though unless I'm formatting or reading/writing to the disk.

2: Swapping drives by typing *DRIVE (0-1-2-3) etc always makes the floppy the current drive no matter which drive I select.

I've took the twist out of a PC floppy cable and that seems to work but I haven't put the BBC twist in between wires 10-12 of the cable. Is this necessary and could this be the cause of the always on drive LED?

Cheers

Mart

[1024MAK]

^5v 1amp (some 2amp) USB adaptors for mobile phones /tablets /cameras /etc:

Yup, they're really useful.

Do be careful that you're buying 'good' ones, unbranded cheapy phone adaptors can be as bad as the one with the hard disk Mate-n-Lok style. (And by 'bad', I mean shock and fire hazards; a search for something like 'cheap charger danger' will find you loads of news stories.)

Incidentally, I have one of the HD ones. It's /very/ light. I fear that there might not be much in the way of components for things like safety.

and for the 12v, use a broadband hub box adaptor, they range from 1amp to 2.5
but need two mains plug sockets, not one

Modern 90mm floppy drives may actually only need 5V, so one of those USB adaptors might well be all you need.

It's also fairly easy to get 5V from 12V. If you don't need much current, then you can easily build a linear regulator (couple of capacitors and an 7805). If you need more, or you want an easy route, it looks like there's a fair few 5V switchmode DC-DC supplies on eBay which would easily do the trick (note, I've not tested these personally, so I'm going by spec).

There are other DC-DC converters. You can go in both directions, step-down, or step-up. But you don't get something for nothing, so check the current requirements. Remember, power in will be the power out plus the conversion losses (most run at 70% to 85% efficiency).

Mains powered adaptors/power supplies/bricks
Yes, I STRONGLY advise you only buy these from well known UK shops / suppliers.
Last year I bought a cheap eBay plug top power supply for the sole reason of investigating the quality and safety. Well, I was not impressed. Cheap construction, poor design (creepage distance, clearance distance of the mains voltage section to low voltage sections), suspect looking components... so I did not bother investigating the transformer (this PSU was a switching type). If you value your life, or that of people around you, just don't bother with them.

Mark

[1024MAK]

I've just added a 3.5 Samsung SFD-321B floppy to my BBC Master and got it working pretty much straight off I've been using some old Amiga disks and can format and do everything else you would expect. However, I could do with advice on a few issues:

1: LED on 3.5 floppy is always lit whether a disk is in or the drive is active. The motor doesn't sound to be active though unless I'm formatting or reading/writing to the disk.

2: Swapping drives by typing *DRIVE (0-1-2-3) etc always makes the floppy the current drive no matter which drive I select.

I've took the twist out of a PC floppy cable and that seems to work but I haven't put the BBC twist in between wires 10-12 of the cable. Is this necessary and could this be the cause of the always on drive LED?

Hi Mart

The BBC computers use the Shugart Associates floppy drive interface. There is just one Motor On control signal (that controls the motors in all the connected drives). But four Drive Select (also known as Device Select) signals. The Drive Select signals are sometimes numbered DS0 to DS3, or DS1 to DS4.

In the past different computer manufacturers used slightly different configurations, so floppy disk manufacturers provided links (jumper shunts) so you could set the drive to the actual signalling used.

I presume the drive you are using does not have these links.

From what you say, it sounds like the Motor On and the Drive Select signals are not connected correctly, or the configuration of the drive is incorrect.

When using a BBC computer with a floppy drive that is set-up to respond to the lowest numbered drive select (say DS0), no crosses in the cable are needed. If you drive was designed for use in a modern PC, it will be set-up for the second drive select (say DS1 if the first drive select signal is DS0). In which case, you can swap the wires around for DS0 and DS1 (pins 10 and 12).

Floppy Diskdrive pinout.
Note that in the Shugart interface list, pin 12 is Device Select 1, not Drive Sel B. The in-use signal on pin 4 on some drives turns on the drive's LED.

PC Floppy Disk Drive Pinout

Mark

[martinjharvey]

Note that in the Shugart interface list, pin 12 is Device Select 1, not Drive Sel B. The in-use signal on pin 4 on some drives turns on the drive's LED.

Thanks for that Mark

I'll open the drive up and check those jumpers out. I have messed with them before when converting a PC drive for use with the Amiga so I know what Im looking for.

As far as the drive light being on constantly is that likely to cause any problems? As I say it doesn't sound like the drive motor is engaged or the heads are moving unless I ask it to format, read etc.

Mart