Adding 2nd A2000 internal floppy drive

[Chuckles]

I've snagged an A2000HD from eBay that had only one internal floppy and wanted to add a second drive, so I hunted down one of the Chinon 354 drives, along with the mounting hardware and installation instructions. I installed the drive and connected jumper J301 on the motherboard as required. When I booted the machine, it booted into Workbench 1.3 from the hard drive, but Workbench displayed a DF1:BAD icon, and DF0: was not recognized at all. In troubleshooting the problem, I've verified this much:

1. With both drives connected to the power supply and ribbon cable, neither one works. Switching connections between drives has no effect. With J301 connected, Workbench reports DF1:BAD, and with it not connected, it doesn't see either drive.

2. With one drive disconnected and J301 disconnected, the remaining drive works fine as DF0:. This would seem to confirm that both drives are in working order, since either drive works when connected as DF0:

Does anybody have any idea what might cause this problem?

[Severin]

YEP

There's a switch or jumper you have to change on the drive... can't remember to what though

Happy researching

[RetroMan]

Just close Jumper 301 on the A2000 Mainboard to add a second internal floppy drive

[Chuckles]

I did close J301 on the mainboard, as I said before. However, it didn't work, so I'm trying to find out why not.

[RetroMan]

Originally posted by Chuckles
I did close J301 on the mainboard, as I said before. However, it didn't work, so I'm trying to find out why not.

Hmmm, works fine for me in 4 different A2000 What kind of cable do you use ???

[Chuckles]

It's the standard 34 pin ribbon cable that was already in the A2000 when I bought it, with connectors for 2 drives, and the standard 4 pin power connectors for each drive. When I install the 2nd drive and close J301, Workbench reports that DF1: is bad whether it has a disk in it or not, and it doesn't see DF0: at all. I wasn't sure if this might be the sort of problem you might have if one of the CIA chips were fried or not, but I'm somewhat doubtful of that.

The other thing that I had thought about was what Severin mentioned, that perhaps when you have two of these drives in an A2000, you might need to change a jumper setting on one of the drives itself. The installation instructions don't mention anything like that though. There is a small jumper block on the rear of the drives with 6 pins, so if that was required, that's where I'd expect to need to change the jumper. The same two pins are jumpered the same way on both drives. I'd be very hesitant to change these though without having more of an idea of what I was doing.

[Chuckles]

After my last post, I did some searching and while I didn't find anything that said exactly what the problem was, I did find an archive on AmiNet with quite a bit of information about various cables and drive connections. It did make reference to device select settings for floppy drives though, so I took a close look at the small jumper block on the Chinon drive and followed the traces to the underside of the PCB where there were printed labels for DS0, DS1, DS2 and DS3. The installed jumper was making the DS0 connection on all 3 of the drives that I had, so I changed the jumper for the 2nd one that I installed into the 2000 to DS1, hooked it back up to the ribbon cable and power again, reinstalled the jumper on J301 on the motherboard, and ...

Voila! Suddenly both floppy drives work perfectly!

(Ok, I know it's not rocket science, but I'm happier than a pig in slop about it.)

Thanks for all your help! I'm a bit surprised that Commodore's installation instructions for the drive don't point out the need to change the jumper on the drive though. I mean, how can a company leave out important information like that and expect to remain in business? (Oops! I think I just answered my own question! )

[Pioneer500]

Noticed AmigaKit sells a floppy drive that works in A2000.

You have to select if its df0 or df1 on checkout, just wondering why?
Can that be changed later by the owner?

Also, what drive is it? , would it work as a PC 720K drive attached to a a2088?

[Djay]

related http://eab.abime.net/showthread.php?t=11781

[DH]

Threads Merged

[Pioneer500]

Thanks for moving my post to a better thread.

So does the Amigakit drive have the jumpers?
Can it work as a standard PC 720K drive on a2088?

[prowler]

Originally Posted by Pioneer500

So does the Amigakit drive have the jumpers?

Floppy drives have a method of selecting whether they respond as DF0: or DF1: when fitted in a big box Amiga (A2000, A4000, etc). This is identical to that used to determine whether a PC floppy drive responds as Drive A: or Drive B:.

The signals are referred to as DS1 (Drive Select 1) and DS2, respectively.

This means that if two Amiga floppy drives are connected to the same data (34-way ribbon) cable, they must be configured to respond to the DS1 and DS2 signals to be selected as DF0: and DF1:, respectively.

This can be achieved in two ways:

1. Alter the jumpers on one of the drives so that they are configured differently - one set to respond to DS1 and the other to DS2.
2. Leave the jumpers on the drives set the same and produce a twist in the cable, so that the DS1 and DS2 lines are interchanged.

So you see that when purchasing a second drive you must specify whether it is to be set to respond as DF0: or DF1:, and this will depend on whether or not you have a twist in your floppy data cable. If it doesn't have a twist, then you will need your new drive set as DF1:, but you will need it set to DF0: if it does.

If AmigaKit are asking that question, then those drives must have the jumpers and they will set them accordingly.

Originally Posted by Pioneer500

Can it work as a standard PC 720K drive on a2088?

I think you will need a PC-compatible floppy drive to attach to your A2088 PC emulator board.

[Pioneer500]

Originally Posted by prowler

Floppy drives have a method of selecting ...

If AmigaKit are asking that question, then those drives must have the jumpers and they will set them accordingly.



I think you will need a PC-compatible floppy drive to attach to your A2088 PC emulator board.

Thanks so much, never used more than 1 floppy before,
great to learn about the jumpers and twisted cables.

My A2088 boots with a 3.5" drive pulled from a Commodore 1581,
which I think is similar or the same as an Amiga drive.
I'll try swapping the 2000 drive and the 1581 drive today, see what happens.

Anyone ever buy the AmigaKit drive , what brand/model is it?

[crashserious]

Originally Posted by RetroMan

Just close Jumper 301 on the A2000 Mainboard to add a second internal floppy drive

So I took this advice (not necessarily from you, Retroman) on my newly received A2000. I had the same drive as the OP as DF0: and a Gotek as DF1:. The drives were working but I wanted to have the Chinon drive as DF1 instead.



When I applied power, I heard a loud pop... which definitely caused a lot of anxiety and then nothing. The screen is blank and it blinks 10 short blinks and 1 long Blink.


Keep in mind, the configuration was working before doing the jumper on J301. Now, after some troubleshooting by swapping chips with a working A500... Paula is for sure dead. I suspect Agnus (8370) is dead as well since they both get warm, but not HOT.

Everything I read points to bad RAM, but While I can't rule it out-- I suspect Agnus is dead as well since she controls RAM as well.

Putting teh Good Paula into the 2000 doesn't help, but the good Paula works after being placed back into the 500. the "bad" paula doesn't work in the 500.


I'm not sure what and where went wrong-- but a word of caution with messing with J301 seems on topic. (Agnus, 2 x CIA, and memory are on order now.)

[Jope]

You ought to unplug your psu from the motherboard and drives and measure all of the output voltages before trying the machine again.

This happening while you powered it up after the jumper change is just an unlucky coincidence.

[Hewitson]

I very much doubt that changing the jumper caused any damage. Maybe it's got a dodgy PSU?

[crashserious]

I agree, it's an unlucky coincidence. I looked at the schematic and I can't see any way this would have caused such a catastrophic failure. It was truly catastrophic. And no, I didn't muck with the jumpers while it was powered up. While some are, not everyone is a complete idiot. Also, voltages were good and looked clean on the scope.


In the end, Agnus, Paula, and Denise were killed/replaced. At that point it was a green screen. Literally was done messing around and socketed all the ram chips, replacing with 32 new ones. Found a CAS trace blown between U526 and U527 that needed repair. Replaced all xx373, xx244, and xx245 logic chips around the memory as well since the wave forms coming out of them looked weird on my Rigol 1054Z Oscilliscope.


Ended with a Yellow screen. No, not the CPU-- Diagrom operates as does the drives and serial output... but replaced CIAs foir good measure. DiagROM showed only 512K of RAM as well.

Cut J300 to enable 512K operation and the 2000 booted into workbench just fine. I have a 8Mb RAM+IDE card-- thinking I don't care anymore since it's working now.

Again, I agree after much work that the jumper should not have caused it... but guess who isn't going to try it again. ;-)

Originally Posted by Hewitson

I very much doubt that changing the jumper caused any damage. Maybe it's got a dodgy PSU?

Originally Posted by Jope

You ought to unplug your psu from the motherboard and drives and measure all of the output voltages before trying the machine again.

This happening while you powered it up after the jumper change is just an unlucky coincidence.