Suitable floppy drive(s) for a Trump-compatible card

[robsoft]

I think Haemogoblin on this Forum found it hard going with a single drive, but I'm not sure if he had a ramdisk on his interface.

Hah, I remember writing software on an expanded Amiga A500 with just single drive when my external floppy broke. Quite frustrating. I can imagine what it will be like! Hopefully just a short-term thing until I figure out what I'm being advised to do with the cable for the second drive etc.

Don't forget, any questions, we'll try to help you. Good luck.

Thank you - I imagine I'll be back again shortly

[1024MAK]

What is the make and model number / type of your drives?

On some, even if there is no conventional jumper shunt/link, a lot have a surface mounted zero ohm "resistor" that can be desoldered and resoldered to the adjacent pads to make the drive respond as the first drive (drive 1).

Mark

[robsoft]

What is the make and model number / type of your drives?

Hi Mark, they're both Sony MPF920s, dated July 2009 although given how cheap you can get 'standard' PC floppies on eBay I'm not above buying a brace of something else if that would make life easier.

There are no jumpers but a couple of visible solder pads with some circuit board marking - I've attached a couple of poor snaps below - I'll do a proper google for the drive and any documentation tomorrow night.

On some, even if there is no conventional jumper shunt/link, a lot have a surface mounted zero ohm "resistor" that can be desoldered and resoldered to the adjacent pads to make the drive respond as the first drive (drive 1).

Cool - thanks. I will investigate this tomorrow - no sign of the card yet and the Russian postal tracking hasn't been updated for a few days so I probably shouldn't expect that imminently - I was warned it might take little while, so I have time to research this

PS sorry for crap quality of pics - found it heard to get light in there, hold the drive steady and get the phone to snap 'em.

[Derek_Stewart]

Hi,

The links on the disk drives should be labelled DS0, DS1, DS2, DS3

DS0 = Drive1,
DS1 = Drive2,
DS2 = Drive3,
DS3 = Drive4,

PC disk drives have all the drives set as DS1 (Drive2), which equates to FLP2 on a QL.

To make a PC drive work on a QL, BBC, Atari ST, you do not need to cut the cables.

I usually straighten all the twists from the PC cable and twist lines 10-12 and make a new connection on the IDC connector, for FLP1.

The best way is to alter the Drive Select links on the drive. Maybe a good idea to get the Disk Drive data sheet.

see thread: http://www.qlforum.co.uk/viewtopic.php?f=2&t=1059

[1024MAK]

At least some Sony MPF920 drives can be modified (there are various different variations of these drives). I'm mobile at the moment. But may be able to add more info later.

Mark

[robsoft]

Cracked it! Thanks everyone for your kind help.

My interface came from Russia today, I plugged it in (wow - ram upgrade! toolkit 2 onboard! hurrah) and immediately started on the floppy drive side of things.

I opened up one of the Sony drives, found the zero-ohm 'jumper' that was 'drive select 1', removed it and soldered-in a tiny tiny jumper wire to bridge 'drive select 0'.
I tested this was now behaving as 'flp1_' by plugging it in to a really simple straight-through floppy cable. Yup, it was floppy one and if I powered everything down and replaced the drive with my otherwise identical other Sony drive, and powered back up, that one was appearing only as 'flp2_'

So then I took a long, standard PC 'twist' dual floppy cable, and carefully removed the IDC connector that was 'after the twist', undid the twist and replaced the IDC connector (a little way before the point at which is was connected before, to avoid the mangling of the original push-in connection). I trimmed the unwanted wire, connected it all up and ta-da! Done - I have a working flp1_ and flp2_, and I can happily copy between them.

Then I formatted a couple of true DSDD disks, then took them over to a PC that I set up with an external USB floppy drive and the wxqt2 tool. I got it configured (it does run in Windows 10 but you need to run the software as 'administrator') and I copied over a few files from the gms\QXL.win folder of my 'The Distribution' download, just making up a couple of real floppies with things like Unzip, breakout and a couple of other games.

I took these back to the QL and they worked just fine - I was even more surprised to see that disks in flp1_ that had a 'boot' program would auto-boot if I reset the QL - for some reason I just expected that to be MDV1_ only kind of thing.

Anyway, all ticking over really nicely now, so my next steps are to tidy this up a bit (wires and bare boards etc) then get a few bits of software to enjoy (probably an adventure game or two) and then - at last! - to start thinking about what I could write/fix/adapt/improve to help contribute to the community.

My final couple of questions for you dual-floppy owners;

a) how are you powering them? I've got an ATX pus from a PC, I've used a breakout board to trick it into powering up and I'm just running the floppies from 2 floppy-type molex connectors. I presume I could get a USB phone-charger type supply and just wire-up the 5v in to both floppies?

b) has anyone got a case or come up with a nice solution to enclosing the floppies? I remember the nice Cumana double-disk drive type enclosures, something neat to hide all that metal and ribbon cable would be nice. I may resort to some Lego Technics in the meantime.

c) has anyone come up with a nice way of covering/protecting the sticking-out section of the trump card? It looks like it's asking for a spillage or a short from a dropped pen etc....

Thanks again for the input. It went much easier than I was expecting it to!

[Derek_Stewart]

Hi,

The original TRUMP Card from Miracle Systems, had a black cover over the exposed circuit board, which also acted as a heat sink of the Trump Card power regulator.

I have replaced the power regulator on my Trump Card with a DC-DC converter, which generates no heat. Which a cover could be made of plastic.

I also thought the ram chips could be replaced by 2 ram chips and reduce the size of the Trump Card. BUt like most things, I have not got this off the drawing board yet.

With regards to the power supply, a plug in wall power supply at 5v would do.

[tofro]

Maybe it's important to mention that the original TC didn't have any cover under the PCB (at least mine doesn't), so it is still possible to short-circuit something on the underside.

I have simply added a sheet of plastic using double-sided tape.

With regards to the power supply: A simple wall wart might not be enough. While most modern 3.5" drives no longer need the 12V supply they normally get in a PC, a single drive typically draws 0.7-0.8 A on the 5V line (depending a bit on the mode of operation). So with 2 drives, your PS should be able to supply at least 2A on the 5V line. (PC specs say 12V/2A, 5V/2A per drive, but the more modern drives don't really need this)

Tobias

[robsoft]

it is still possible to short-circuit something on the underside.

good point! Good idea regarding the sheet, too.

So with 2 drives, your PS should be able to supply at least 2A on the 5V line.

ah, that sounds like it's the kind of PS that the Raspberry Pi needs - I do have a few beefier 5v wall warts kicking around. I'll get a pin diagram for the molex connector and have a go, it would be nice to lose that huge PC ATX PSU from the desk!

Thanks!

[georgeo]

Hi Robsoft,

It sounds like you are on a similar journey to me, though I bought a pre-assembled dual, floppy disk drive, as I have no soldering skills.

I'd also be interested to hear if anyone makes a protective case for the Trump card clone. I have two inquisitive young children, so it seems only a matter of time before something bad happens to the exposed electronics.

Also, how are you getting on with your setup? I'm seeing intermittent problems when accessing the floppy disks, though don't know if this is a well-known driver niggle, a problem with my QL, Trump card, or floppy drives:

http://qlforum.co.uk/viewtopic.php?f=2&t=1623