New Cat repairs.

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Marcin Wichary

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Nov 8, 2017, 5:59:07 PM11/8/17
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Hi! New group member and new Cat owner here.

I recently got my own Cat. I cleaned it up and restored (documented here on Twitter), but the floppy drive swallowed my disk and won’t spit it out if I press the button. The floppy also started making a noise.

Upon trying to open the case, I noticed one of the screws is stripped. As I’m waiting for my anti-stripped-screw tools to arrive, any advice on dealing with an opened Cat particularly the CRT (I don’t intend to do anything with it, but I’m scared of it – I have zero experience) and the floppy drive itself?

Thank you in advance!

Marcin

dwight

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Nov 8, 2017, 7:17:53 PM11/8/17
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If you haven't pulled too hard on the disk, it is a good chance it can be repaired.

If in your frustration you yanked the disk out, you will have destroyed the head assembly.

The disk drives are almost impossible to find but there are options.

As for the screw, I wish you good luck. Once open, I can describe how to remove the

drive and fix it.

Dwight



From: cano...@googlegroups.com <cano...@googlegroups.com> on behalf of Marcin Wichary <mwic...@gmail.com>
Sent: Wednesday, November 8, 2017 2:53:20 PM
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Subject: [Canon Cat] New Cat repairs.
 
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Marcin Wichary

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Nov 8, 2017, 7:47:30 PM11/8/17
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Dwight, thanks for a prompt response! I didn’t yank the disk out at all – just tried in vain to press the eject button.

Would you mind explaining removing the drive now? With luck, I might open it tomorrow morning already. Thank you so much in advance!

Marcin

On Wed, Nov 8, 2017 at 4:17 PM, dwight <dke...@hotmail.com> wrote:

If you haven't pulled too hard on the disk, it is a good chance it can be repaired.

If in your frustration you yanked the disk out, you will have destroyed the head assembly.

The disk drives are almost impossible to find but there are options.

As for the screw, I wish you good luck. Once open, I can describe how to remove the

drive and fix it.

Dwight



From: cano...@googlegroups.com <cano...@googlegroups.com> on behalf of Marcin Wichary <mwic...@gmail.com>
Sent: Wednesday, November 8, 2017 2:53:20 PM
To: cano...@googlegroups.com
Subject: [Canon Cat] New Cat repairs.
 
Hi! New group member and new Cat owner here.

I recently got my own Cat. I cleaned it up and restored (documented here on Twitter), but the floppy drive swallowed my disk and won’t spit it out if I press the button. The floppy also started making a noise.

Upon trying to open the case, I noticed one of the screws is stripped. As I’m waiting for my anti-stripped-screw tools to arrive, any advice on dealing with an opened Cat particularly the CRT (I don’t intend to do anything with it, but I’m scared of it – I have zero experience) and the floppy drive itself?

Thank you in advance!

Marcin

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David Young

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Nov 9, 2017, 11:37:20 AM11/9/17
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On Wed, Nov 08, 2017 at 04:32:13PM -0800, Marcin Wichary wrote:
> Dwight, thanks for a prompt response! I didn’t yank the disk out at all –
> just tried in vain to press the eject button.
>
> Would you mind explaining removing the drive now? With luck, I might open
> it tomorrow morning already. Thank you so much in advance!

Dwight,

My drive has not broken, but I would like to repair it before it does,
so I would also be grateful for any instructions you can provide.

Dave

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Santo Nucifora

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Nov 9, 2017, 11:56:18 AM11/9/17
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Since this discussion came up, can that floppy drive part be 3d printed? 

Jonathan Gevaryahu

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Nov 9, 2017, 12:03:30 PM11/9/17
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I'm guessing no, since I believe the problem to begin with is that the part is made of plastic instead of metal.
I think the correct solution is to cnc-mill a replacement piece out of aluminum or steel, or just make it yourself using a drill press etc.
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dwight

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Nov 9, 2017, 2:55:15 PM11/9/17
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The part is intended to work like a spring, holding the head guide rod in place. It is made of what looks like nylon. This is not a particularly good material when put under stress. As it ages, it become more brittle. In this case, if it hasn't failed, it is just luck.


As for how to repair. We had some pictures posted some time back but goole in is wisdom determined that these were no longer needed.

Still, on opening the disk drive, the location of the failure will be obvious. There is a tab at the end of the guide rod. Every disk that I've looked at, one can see a fracture across this tab, even on those that have not yet failed.

I repaired mine with a plastic tab of a different type of material ( I'm not sure what it was but flexing it showed no sign of cracking or failing.

One can of course glue the rail down with some JB Weld ( a metal filled type of gray epoxy found at US hardware and auto parts stores ). One does have to be careful that it doesn't block the normal full travel of the head assembly.

I think Jack has picture of the drive apart. I may have these someplace but it was a few years ago. I was thinking we might put some of these on another computer forum that can keep such photos. Maybe the VCF forum would be good as it is used by many and easily searched, using google search ( note that using the forum search with words of less or equal to 3 letters fails. CAT, KIM, even VCF will return no results so use the google search ).



From: cano...@googlegroups.com <cano...@googlegroups.com> on behalf of Jonathan Gevaryahu <jgeva...@gmail.com>
Sent: Thursday, November 9, 2017 9:03:27 AM
To: cano...@googlegroups.com
Subject: Re: [Canon Cat] New Cat repairs.
 

dwight

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Nov 9, 2017, 3:00:11 PM11/9/17
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I should note that even though the tab was held in place with a screw, that was only there to hold it long enough for a pin that went through the frame to be staked. In other words, it was not intended to be removed.

The gluing method is as valid as any.

Dwight



From: dwight <dke...@hotmail.com>
Sent: Thursday, November 9, 2017 11:55:13 AM

Charles Springer

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Nov 9, 2017, 4:28:06 PM11/9/17
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I still have a pair of NIB drives from the prototype days that are single sided or something like that. I wonder if the part is the same? They can be for replacement parts, or to measure for CNC/3D printing.

-- Charlie

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dwight

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Nov 9, 2017, 7:06:12 PM11/9/17
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The part that fail is not truly removable. It is staked to the frame. I don't believe it has to be made exactly the same.

The piece I made is just a flat piece in a tear drop shape. I drilled a small hole and used the screw that was there originally. I did not replicate the small post that went through the frame and was staked from the other side. The flat tear drop shaped part could be easily created on a 3D but the small pin going through the frame would be tough as I recall it was only about .03 to .05 inches in diameter someplace. With the screw holding it down, I felt the pin was redundant.

It is possible for the screw to come loose and allow the piece to rotate but I don't think that is a likely problem.

If one worried about this, I'd think it would be better to dill a hole where the post went through and glue a pin to the tear drop piece. Then the screw would have to be really loose to cause any issue.

The only issue with 3D printing is the ability of the plastic to not creep or fracture over time like the original piece.

Looking back at what could be done, I'd be happier with the JB Weld.


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Sent: Thursday, November 9, 2017 1:28:04 PM
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Marcin Wichary

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Nov 10, 2017, 6:51:09 PM11/10/17
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Okay, I got in, but I need a bit more help. 

I opened a drive and then removed a floppy disk that was stuck there – I’d hope without adding to the damage.

The head assembly was just… floating there. It was on the stepper motor on one side, and in between the black part on the other. But I could easily get it out.

It seems clear that it should be firmly attached to something, but I’m not sure what. It doesn’t seem obvious to me what broke off or detached to cause it. Would appreciate any suggestions.

Here’s the photo of the current state, with the head assembly put on top of the cage.





Marcin Wichary

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Nov 10, 2017, 6:52:38 PM11/10/17
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(With the head mechanism out of the way, I can put the disk back in and out without problem, so that part’s working.)

Marcin Wichary

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Nov 10, 2017, 7:02:08 PM11/10/17
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Ah, by comparing to other photos, it’s starting to look as if the floppy drive has already been damaged like other people mentioned here – am I right in seeing that the head has been ripped out? 

dwight

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Nov 10, 2017, 7:24:58 PM11/10/17
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As I recall, You need to do some more disassembly. The tray assembly that holds the disk needs to be removed. I seem to recall you need to remove the ejector assembly. To do that you first need to release the long spring. Then you should be able to remove the black screw holding things together.

The frame should then be able to slide backward and released at the 4 post, 2 on each side. It will lift straight up once it slides back.

Don't force anything. The thin plastic piece that is latched under the hook at the back may need to be released as well. I think it releases by rotating the finger and lifting it. It would have a pin through the tray assembly.

You can see the failed part. Right where the thin black piece is latched, the finger sticking towards the back is right over the silver screw that would be holding the tension. The rod would be held by the missing tab piece that broke off, right at the screw. You might look for the small missing piece of white plastic to be able to reconstruct things.

Once the tray is out of the way, you should be able to see how the guide rod on the head assembly sits along the side,

Before getting too carried away with the disassembly, you might want to inspect the head, The pressure pad is just held down with a spring, you can lift it enough to inspect the head. It is on a floating spring mount. It should sit flat and straight.

It has been a long time so work carefully and don't force anything. I do recall that when done right, it almost fell apart.

Dwight




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Sent: Friday, November 10, 2017 3:52:17 PM
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dwight

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Nov 10, 2017, 7:32:31 PM11/10/17
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I should note that I think the head cable can be removed at the PC board, by pulling it from the connector.

Look carefully first as the may be a release for it but it may just pull out.

Dwight


From: dwight <dke...@hotmail.com>
Sent: Friday, November 10, 2017 4:24:56 PM

Marcin Wichary

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Nov 10, 2017, 7:33:12 PM11/10/17
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Thank you, Dwight, for your help. Unfortunately, I have confirmed that the head is simply no longer there – you can just see the dangling connector where it used to be. :·( I’m afraid swapping the head from another floppy drive is a bit above my pay grade at this moment. (Would that even work, hypothetically?)

I will first focus on trying to connect the Cat to a modern computer via a null-modem cable. Please someone tell me this is possible. :·)


dwight

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Nov 10, 2017, 7:39:59 PM11/10/17
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Hi

 I'm not sure what RS232 connection you'll need. I you need to use a light box for that. In the setup menu you tell it that the serial is the printer port.

You might post a picture with the pressure pad out of the way so others can see the damage.

I don't know of anyone that is skilled in attaching a read/write head and aligning it.

Too bad, people insist on removing the disk by force. Most of these could be saved with just a little patience.

Dwight



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dwight

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Nov 10, 2017, 8:42:25 PM11/10/17
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There is a way to use the serial port to transfer the text to another CAT through the serial but I couldn't even guess the protocol.

Dwight


From: dwight <dke...@hotmail.com>
Sent: Friday, November 10, 2017 4:39:39 PM

Charles Springer

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Nov 11, 2017, 9:28:43 PM11/11/17
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Maybe I aught to make a little emulator that takes an SD card. Round up all those old cards that are a few MBytes. They must be sold by the pound now if you can find them. Or it could bluetooth to your phone for emulation.

-- Charlie

On Thu, Nov 9, 2017 at 4:06 PM, dwight <dke...@hotmail.com> wrote:

Charles Springer

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Nov 11, 2017, 9:31:50 PM11/11/17
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A floppy emulator that is.

Charles Springer

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Nov 11, 2017, 9:37:22 PM11/11/17
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Can you take a close-up of the end of the assembly away from the cable bits? The end part can sort of open and close a little for when a diskette is slid in.

On Fri, Nov 10, 2017 at 3:50 PM, Marcin Wichary <mwic...@gmail.com> wrote:

David Ryskalczyk

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Nov 11, 2017, 9:44:21 PM11/11/17
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If I were doing this (no time at the moment) I’d probably see about making an adapter board to use a common Gotek adapter (widely available on Amazon or eBay) with the FlashFloppy firmware that Keir Fraser developed for it which is available at https://github.com/keirf/FlashFloppy .

David

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Mark Wills

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Nov 14, 2017, 12:01:37 PM11/14/17
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It's time to replace these drives with something modern that can prolong the life of these machines.

A USB Floppy Emulator should do the trick.

dwight

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Nov 14, 2017, 12:29:01 PM11/14/17
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As I mentioned before, these are file based emulators. If you don't have specific code to handle your particular format, these won't work. The Cat's disk are not file based.

Have you written code for the STM32 with a On-The-Go USB interface?

I've started looking into these but it will tak a lot more work.

Dwight



From: cano...@googlegroups.com <cano...@googlegroups.com> on behalf of Mark Wills <markwi...@gmail.com>
Sent: Tuesday, November 14, 2017 9:01:36 AM
To: Canon Cat
Subject: [Canon Cat] Re: New Cat repairs.
 

David Ryskalczyk

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Nov 14, 2017, 12:34:45 PM11/14/17
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Dwight,

There’s alternate open-source firmware that Keir Fraser wrote for these STM32-based Gotek emulators available at https://github.com/keirf/FlashFloppy — so far it does seem to work pretty well.
This does support HFE format intended for the HxC floppy emulator, which should be adaptable for Canon Cat - with some work.

An adapter to connect the 20 pin flat flex cable to the 34-pin floppy port would be necessary, too.

David

Jonathan Gevaryahu

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Nov 14, 2017, 1:30:17 PM11/14/17
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Speaking of the old dead drives some users here have, I'm interested in getting the disk head controller interface microcontroller decapped, if someone has a dead drive they are willing to part with.

(I'm actually rather curious what that microcontroller actually does, since on most floppy drives I've seen there is a fixed ASIC used rather than a microcontroller...)
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dwight

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Nov 14, 2017, 1:46:31 PM11/14/17
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This data from the disk is stored as files on the USB memory. It assumes that there is a file structure on the floppy.

Of course, the code could be modified. It needs to treat the entire floppy as a single file. I'm not saying it is impossible just that it is not an off the shelf software. A lot of effort would be needed.

I'd love to see it done.

I personally have another machine that I'd like to use one of these for. It is not currently supported by HxC and I doubt it ever would be.

I have bought one of the Gotek units.

Dwight



From: cano...@googlegroups.com <cano...@googlegroups.com> on behalf of David Ryskalczyk <d23...@gmail.com>
Sent: Tuesday, November 14, 2017 9:34:39 AM
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Subject: Re: [Canon Cat] Re: New Cat repairs.
 

dwight

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Nov 14, 2017, 1:59:47 PM11/14/17
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Hi Jonathan
 I never looked carefully at the controller board to notice that it was a uC there.
Dwight



From: cano...@googlegroups.com <cano...@googlegroups.com> on behalf of Jonathan Gevaryahu <jgeva...@gmail.com>
Sent: Tuesday, November 14, 2017 10:30:12 AM

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Subject: Re: [Canon Cat] Re: New Cat repairs.

Jonathan Gevaryahu

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Nov 14, 2017, 2:44:10 PM11/14/17
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The cat schematics show it, its likely a sharp, nec, or epson 4-bit MCU, though which type I'm not entirely sure.

dwight

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Nov 14, 2017, 2:48:07 PM11/14/17
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I take it back, the HFE format is a 512 byte bit image of the disk.

I only see DD formats in the HFE document, though.

I think we need to run some experiments to see what happens.

Dwight



From: cano...@googlegroups.com <cano...@googlegroups.com> on behalf of Mark Wills <markwi...@gmail.com>
Sent: Tuesday, November 14, 2017 9:01:36 AM
To: Canon Cat
Subject: [Canon Cat] Re: New Cat repairs.
 
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