Share your knowledge on these two classic MPCs
By infinit Sun Oct 05, 2014 1:33 am
Did some research but couldn't find any answers. Looking to see if their is a simple solution to this problem, when i load a floppy on boot with the mpc300 it loads fine, the problem is trying to load a second floppy disk. It will still display all the information from the first disk, this also hurts me when I'm trying to save several things to multiple disks.

Has anyone else experience this problem? If so what is the fix, I'm thinking about replacing the floppy altogether. Yes I have a zip drive but it's broken at the moment so floppies are my only way to save my work.
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By SimonInAustralia Sun Oct 05, 2014 3:10 am
Have you noticed that problem with it before, has it ever worked correctly?

Is it the original drive, or a replacement?

Maybe it is a replacement, and the disc change jumper is not set correctly, so it is not sending a disc change message to the MPC, or it is sending that message on the incorrect wire in the cable for the MPC to recognise it, when you swap floppies.
By infinit Tue Oct 07, 2014 6:15 am
SimonInAustralia wrote:Have you noticed that problem with it before, has it ever worked correctly?

Is it the original drive, or a replacement?

Maybe it is a replacement, and the disc change jumper is not set correctly, so it is not sending a disc change message to the MPC, or it is sending that message on the incorrect wire in the cable for the MPC to recognise it, when you swap floppies.


Yes it has worked correctly in the past. I do believe it's the original drive, although I did buy the Mpc used. I was using the zip drive for a year, and at the same time saving my drums to floppy disks. Never had this problem until the zip drive went out and I started saving everything to floppy.

I have opened the Mpc before but never touched the floppy drive, is this something I could fix myself? If so what needs to be done.
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By SimonInAustralia Tue Oct 07, 2014 7:56 am
For some reason it isn't sending a disk change signal from the drive to the MPC.

There is a sensor inside the drive that detects disk changes, and sends a disk change signal on pin 34 of the connector/cable.

First thing to do might be to open up the MPC and re-seat the floppy drive cable, in case it isn't making contact correctly.

Then you might want to check the make/model of the drive, find a manual or list of jumper settings for that particular drive, and make sure that the disk change (DC) jumper is where it should be, in case it has come loose or is missing.

Next might be to try and clean the disk change sensor, in case it is dirty.

Last option might be to replace the drive with a new one.
By Clint Tue Oct 07, 2014 8:00 am
Maybe it was working before, but did you ever have to change disks or were you saving to one floppy?

The fix would be to ensure that the jumpers on the floppy drive are correctly placed, particularly the DC disk change. You might need to remove the drive to get a good look at the jumper block.
By infinit Thu Oct 09, 2014 9:34 pm
Yes I have saved to multiple disks before. I have the mpc open and floppy drive out. It's a Teac FD-235HF (P/N 19307765-00), I just need to find the jumper settings as you described.
By infinit Thu Oct 09, 2014 9:47 pm
Alright I found this, http://embeddedsw.net/EMUFDD_TEAC_Jumpers.html

It's second to the bottom of the page, "Medium TEAC Drives" I don't have a clue about what I need to change. This is a picture of my current jumper settings, It looks like the pin is missing on the "DC"

E1-E2 : DC34 Disk Change output on Pin 34
E1-F1 : DC2 Disk Change output on Pin 2

Image
Last edited by infinit on Thu Oct 09, 2014 10:03 pm, edited 1 time in total.
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By SimonInAustralia Thu Oct 09, 2014 10:01 pm
If it worked before, and doesn't now, you shouldn't have to change anything.

Maybe just confirm that the DC34 (Disk Change = Pin 34) jumper is where it should be.

I would guess that the drive needs to be replaced.

The documentation I have seen suggests that the disk change sensor is a switch, so not an optical sensor that might be dirty and can be cleaned.

Are there a set of numbers in after FD-235HF, that specify the exact version of FD-235HF that you have, as there are different types.

If re-seating the floppy cable doesn't work, and the DC34 jumper is in place, maybe time for a new floppy drive.

If a new floppy drive doesn't work, maybe something is wrong with the floppy cable/connector, or the MPC PCB.
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By SimonInAustralia Thu Oct 09, 2014 10:04 pm
infinit wrote:Alright I found this, http://embeddedsw.net/EMUFDD_TEAC_Jumpers.html

It's second to the bottom of the page, "Medium TEAC Drives" I don't have a clue about what I need to change. This is a picture of my current jumper settings, It looks like the pin is missing on the "DC"

E1-E2 : DC34 Disk Change output on Pin 34
E1-F1 : DC2 Disk Change output on Pin 2

Image

Maybe try moving the jumper that is currently connecting D2 to E2, so that it connects E1 to E2 instead.

But not sure why it worked before, and doesn't now.
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By SimonInAustralia Thu Oct 09, 2014 10:10 pm
But my floppy jumper block looks exactly the same as yours, with the jumper on D2-E2, meaning that it is outputting a Ready signal on pin 34, rather than a Disk Change signal on pin 34, and it works as it should.

So not sure, maybe the MPC3000 doesn't actually need a Disk Change signal on pin 34 after all.

Might be time for a new drive, if re-seating the floppy cable has not helped.

But even a new drive is no guarantee that it will work, and that something else is not wrong with your MPC.
By infinit Thu Oct 09, 2014 10:37 pm
I tried moving the jumper from D2/E2 to E1/E2, it won't even load or recognize the floppy disk. Your right maybe it's time for a new drive, at least I hope that's the issue.
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By SimonInAustralia Thu Oct 09, 2014 10:57 pm
I checked the MPC3000 schematics, and pin 34 is used for a Ready signal, not a Disk Change signal, so your initial jumper settings were correct.

That means that it does not use a Disk Change signal.

So I now guess that maybe it is some sort of problem with your MPC, rather than the floppy drive. But that is a very uneducated guess!
By infinit Thu Oct 09, 2014 11:18 pm
SimonInAustralia wrote:Did you put it back to where it was, and test it again?


Yes I put everything back and tested again, it does the same thing as before. It will load the first floppy but wont allow me to load a second floppy. The load screen still shows the data on the first floppy disk. I also wonder if my mpc is messed up.