• Please review our updated Terms and Rules here

Toshiba T1910CS floppy drive

P

Papalapa

Experienced Member
Joined
Mar 5, 2024
Messages
91
Location
Barcelona
Hi, I'm a retro-computer collector and actually I'm repairing a Toshiba T1910CS laptop.

The computer correctly starts up but floppy drive is not able to read any disk, and hard drive seems to be dead. Therefore is not possible to load any Operating System nor software

I completely dissasembled the computer to gain access to the power supply board because I've had in mind to replace the whole capacitors, but I was surprised when I've seen that this job was already done by someone. Carefully checking, I discovered an sticker with a number on it that I guess was set by a Technical Service. As you know the main problem of these aged laptop computers is the power supply capacitors so, I guess that time ago the computer have had this problem and was sent to the Technical Service for repair.

I connected the hard disk (200MB) to another laptop and using Norton Utilities under DOS and Hiren's Boot utilities I recovered sectors, marked the bad ones, restored partitions and MBR, and finally I was able to install MS-DOS 6.22 so, the HD has been recovered.

The main problem now is the floppy drive. It's a Citizen ZA096805 drive. Once dissasembled I found the belt completely damaged. I used to see broken belts with the rubber cracked, but this one was sticky and attached to the motor shaft. It was necessary a cotton swab with isoprophylic alcohol and a lot of patience to leave the area clean. Here's a picture:

IMG_3855.JPG

Finally, I replaced the belt by a new one from my stock and we will see it this works because I have no idea of the origina lenght of the belt. Anyway, the main question and the origin of this post is to ask if someone knows which is the kind of connector and cable that this drive has. It's not the typical 34-pins connector, it has a flat cable. If I do not succeed to repair the drive maybe I can find another compatible with this connector. I have a 3,5" IBM drive with a flat cable but has less pins that this one so, not compatible. Here's the picture:

1.jpg

Thank you!
 
We need a better picture of the the connector. But does it take a mylar ribbon and is there a lift to release plastic retaining clip that holds the ribbon in place? If so then many laptop floppy drives use this connector. Size of the drive and side of the drive that the connector is on differs from brand/model. Teac or Panasonic make nearly square shaped floppies and Citizen and others make rectangular (deeper than wide) drives.
 
These Toshiba T1900 series laptops use an older variety of the flat notebook floppy drive connector, it has a wider pin spacing and different pinout I believe than most later drives. I believe the pinout is listed in the service manual. I’d like to build an adapter at some point to allow use of a more modern direct-drive FDD like a Teac or something. I think it would be far wiser to spend time on that then to hope by chance you get a belt that works. It’s far too hit-and-miss with the replacement belts to make it worth the effort in my opinion.

I think the form factor of the drive is pretty standard on these, so I don’t think physical fit should be an issue, though I haven’t confirmed 100%.

Otherwise I think these are very good laptops. I have had a T1960CT for many years and it’s a really solidly built unit. The plastic on these has aged a lot better than the later gray Toshibas. My poor T1960CT actually took a hell of a fall onto a hard surface while I was moving once, and it didn’t even leave a mark on it.
 
What is the width of the connector? If it is ~26.0 mm, it is a 1.00mm pitch 26 position FFC cable. If it is significantly larger than 26.0mm, then it is a 1.25mm pitch 26 position FFC cable. 1.00mm is much easier to deal with since it is a modern standard. 1.25mm is no longer a standard that anyone uses and hasn't used since the mid-90s. If it is 1.00mm you have your choice of options, including 1.00mm direct-drive floppy replacements. If it's 1.25mm, your first stop is going to be a 1.25 to 1.00mm FPC cable or a 1.25mm to 1.00mm FFC adapter so you can be compatible with any of the modern options (or a rather expensive 1.25mm to 34 pin adapter sold by one company that charges outrageous shipping if you don't live in Europe, but I discourage people from choosing this option just due to my distaste of shipping costing the same amount as what is already an overpriced piece of simple electronics)
 
Last edited:
Paralel said:
What is the width of the connector? If it is ~26.0 mm, it is a 1.00mm pitch 26 position FFC cable. If it is significantly larger than 26.0mm, then it is a 1.25mm pitch 26 position FFC cable. 1.00mm is much easier to deal with since it is a modern standard. 1.25mm is no longer a standard that anyone uses and hasn't used since the mid-90s. If it is 1.00mm you have your choice of options, including 1.00mm direct-drive floppy replacements. If it's 1.25mm, your first stop is going to be a 1.25 to 1.00mm FPC cable or a 1.25mm to 1.00mm FFC adapter so you can be compatible with any of the modern options (or a rather expensive 1.25mm to 34 pin adapter sold by one company that charges outrageous shipping if you don't live in Europe, but I discourage people from choosing this option just due to my distaste of shipping costing the same amount as what is already an overpriced piece of simple electronics)
Click to expand...
Thank you all for the information, it's clear now.
@Paralel, I live in Barcelona so, Europe Which is this company that you talk about?.
 
Papalapa said:
Thank you all for the information, it's clear now.
@Paralel, I live in Barcelona so, Europe Which is this company that you talk about?.
Click to expand...

The company is:

FlexiDrive - Floppy Drive Update

floppyemulator.com floppyemulator.com

This is the 34 pin to 26 conductor you would need if it is indeed 1.25mm:

34-26 Pin P1.25 Adaptor | FlexiDrive - Floppy Drive Update

floppyemulator.com floppyemulator.com

This is the 34 pin to 26 conductor you would need if it is instead 1.00mm:

34-26 Pin P1.0 Adaptor | FlexiDrive - Floppy Drive Update

floppyemulator.com floppyemulator.com

If you just want to get the 1.25 to 1.00mm adapter board instead, assuming you are dealing with a 1.25mm interface, this is what you would want:

26-Pin 1.25 To 26-Pin 1.00 FPC Adapter | FlexiDrive - Floppy Drive Update

floppyemulator.com floppyemulator.com

There is a guy on what I understand to be like something like the Polish version of eBay/Craigslist that also sells the same adapter for far less:

allegrolokalnie.pl

Floppy Adapter 26Pin 1 25mm do 26Pin 1 00mm FPC | Warszawa | Kup teraz na Allegro Lokalnie

Kup teraz: Floppy Adapter 26-Pin 1.25mm do 26-Pin 1.00mm FPC za 49,00 zł i odbierz w mieście Warszawa. Szybko i bezpiecznie w najlepszym miejscu dla lokalnych Allegrowiczów.
allegrolokalnie.pl allegrolokalnie.pl

I have encountered a case recently involving a Toshiba floppy that was similar to your situation and a slight modification of the 34 pin to 26 conductor adapter was necessary in order to make it work with the Toshiba system. The required modification is the need to jumper position #8 on the 26 conductor interface, to Ground, because the Toshiba systems place the Ready signal at position #8 which is very odd, and most adapters are not wired to deal with such an unusual situation. Without jumpering position #8 on the 26 conductor interface to Ground any attempt to access a floppy or floppy emulator through the adapter would always return a "Drive Not Ready" error.
 
After trying 4 different belts of my own stock, none of them worked. When the motor starts to turn or after a few seconds I get an error message and after opening the drive I can see the belt out of place. I found an original belt in eBay but as the drive is also an old model I’ll try to replace it by an IBM one that also have at home. This is direct-drive (no belt) and the connector is 1.00 mm instead of 1.25mm.

I already ordered the 26pins 1mm to 1mm flat cable and meanwhile I’ll check the pin assignement of each drive to be sure that are compatible.
 
I have some really exciting info to add about the floppy drive in these laptops! Turns out, the pinout IS standard! I was looking at it in the service manual comparing it to the TEAC FD-05 and realized it matched up 100%! What isn't standard however is the pin spacing on the drive itself, but the connector on the motherboard has the standard pin spacing! So, I hooked up a TEAC FD-05 series drive using a different ribbon cable borrowed from another laptop, and it works great!

I tried this out on the project T1910 (monochrome) I just got. I have another on the way and I'm going to make one good one out of the two. I've wanted a monochrome 1900 series for ages! The mono screen looks really good.

So, looks like I will be ordering some more cables and drives and upgrading both my T1960CT and my new T1910 to direct-drive floppies! It will be insanely cool to FINALLY have working, reliable diskette drives on these laptops. That will truly make them pretty much perfect vintage laptops in my opinion, because the floppy was really my only complaint with them.
 
compaqportableplus said:
I have some really exciting info to add about the floppy drive in these laptops! Turns out, the pinout IS standard! I was looking at it in the service manual comparing it to the TEAC FD-05 and realized it matched up 100%! What isn't standard however is the pin spacing on the drive itself, but the connector on the motherboard has the standard pin spacing! So, I hooked up a TEAC FD-05 series drive using a different ribbon cable borrowed from another laptop, and it works great!

I tried this out on the project T1910 (monochrome) I just got. I have another on the way and I'm going to make one good one out of the two. I've wanted a monochrome 1900 series for ages! The mono screen looks really good.

So, looks like I will be ordering some more cables and drives and upgrading both my T1960CT and my new T1910 to direct-drive floppies! It will be insanely cool to FINALLY have working, reliable diskette drives on these laptops. That will truly make them pretty much perfect vintage laptops in my opinion, because the floppy was really my only complaint with them.
Click to expand...
We have followed the same way :). After checking the drive & board pinouts I found that are compatible and I already ordered a 1mm. flat cable. It's like this one but with the silvered conatcts on the other side of the cable. 10cm only is enough.
flex.jpg
On the other hand I also found an original belt for the original Citizen drive so, I'll try to repair the drive even if I leave the IBM drive installed. We will see...
 
Papalapa said:
We have followed the same way :). After checking the drive & board pinouts I found that are compatible and I already ordered a 1mm. flat cable. It's like this one but with the silvered conatcts on the other side of the cable. 10cm only is enough.
View attachment 1280505
On the other hand I also found an original belt for the original Citizen drive so, I'll try to repair the drive even if I leave the IBM drive installed. We will see...
Click to expand...
Very nice! Thanks for the info on the cable length, I was wondering which size I should get and that helps me a lot.
 
compaqportableplus said:
Very nice! Thanks for the info on the cable length, I was wondering which size I should get and that helps me a lot.
Click to expand...
Be in mind that 10cm. is enough in my case because the IBM drive has the connector in the left side instead of the right side (as the original Citizen drive).
In this picture you can see the provisional connection just for testing purposes, but in this case I made a mistake ordering the flat cable with the silvered contacts in the same side. That's why I ordered now the right cable and I'm waiting to receive it.

IMG_3878.JPG
 
Just as an FYI for anyone who wants to order a similar FFC (flat flexible cable), the most common terminology for an FFC where the contacts are on the opposite side on either end is "reverse cable", whereas an FFC that has the contacts on the same side on both ends is known as a "forward cable".

I'm glad to see that your replacement was much easier than in the Toshiba models that have the older 1.25mm interface.
 
Bad news: after after several tests with two different flat cables and two floppy drives, I realized that the problem is the floppy controller itself. Sometimes it issues a reading error message, sometimes shows a message saying the the floppy cannot be read, etc..

As I'm not able to locate and replace the controller chip, finally I installed Norton Commander SOFTWARE and connected a null-modem cable to the serial port to transfer software from another computer. Due to the lack of USB port, CD-ROM, and network socker this is the only way that I found.
 
Some update to this post after more than one year :):
After unsuccesfully trying a TEAC FD-05 and a MITSUMI D353F3 drives I was thinking that the diskette controller of the laptop was damaged, but I was wrong. Today I connected a CITIZEN U1DA drive and worked like a charm. The problem is that isn't an slim drive and do not fits inside the Toshiba laptop. I'm trying to find the CITIZEN U1DA pin assignments to compare with the TEAC and MITSUMI drives but was impossible for me to find it.

Anyone has this information?
 
Papalapa said:
Some update to this post after more than one year :):
After unsuccesfully trying a TEAC FD-05 and a MITSUMI D353F3 drives I was thinking that the diskette controller of the laptop was damaged, but I was wrong. Today I connected a CITIZEN U1DA drive and worked like a charm. The problem is that isn't an slim drive and do not fits inside the Toshiba laptop. I'm trying to find the CITIZEN U1DA pin assignments to compare with the TEAC and MITSUMI drives but was impossible for me to find it.

Anyone has this information?
Click to expand...
Forget it about this, I made a mistake and I have done this test with the Toshiba T1800, not the T1910CS of the post.

On the T1910CS I tested three different disk drives, 2 Mitsumi D353F3 and 1 TEAC FD-05HG with the same results: General reading errors, error message while trying to format them, and only one time I have seen the files after the DIR command was typed. In all the cases the diskette starts to turn and after 5 times hearing "clik-clik" the diskette stops and an error is issued.

The TEAC FD-05HG perfectly works in another computer. Any idea about what's happening?
 
Well, it seems that Toshiba T1850 and T1910CS they don't like direct-drive units. After several drive/laptop/cable combination here are the results:


table.png

That's crazy :eek:
 
I believe the likely reason is probably because the laptop was designed before the later slimline floppies were produced. Later Japanese slimline floppy drives actually support 3 types of floppies, thus they are called "3-mode" drives.
They support 720k, 1.2m, and 1.44m.
1.2M is a japanese-only drive mode that uses a different RPM.
However, these newer floppy drives use Pin 13 as a MODE SELECT pin. If it is floating or grounded, the floppy will FAIL to read HD 1.44m disks because it will try to read them as 1.2m! However, it will read DD 720k disks fine. If you try any of your drives with a 720k disks they will probably work fine.

The solution is to cut and then pull high the floppy drive's pin 13 so that it stays locked into 720k/1.44 modes. Or, you can order a Teac FD-05HF which is the same as your FD-05HG except it doesn't support 1.2m and you shouldn't need to modify the adapter cable.

I've attached part of the spec sheet for the D353F3 that shows the offending mode enabled (low) or disabled (high) by pin 13.
 

Attachments

  • 3 mode drives.png
    3 mode drives.png
    519.7 KB · Views: 7
This is incredibly helpful, I have my old Toshiba T1910CS which I have owned from new, just dusted it off and wanted to get it back up and running. Ive sourced a 16mb JEIDA ram card upgrade which worked, and as the original 200mb hard drive seems to have packed in Ive fitted an ide to CF with a WD 512mb CF Silicon Drive which is also detected fine in the bios. My next problem was the floppy drive which has also given up so with the info above ive ordered a 26pin flat ribbon and one of these - https://www.aliexpress.com/item/400...der_detail.order_detail_item.3.2c00f19cBnulrf SFR1M44-DU26 GOTEK USB/FLOPPY TRANSDUCER FLOPPY EMULATOR 12.9MM Thickness which I'm hoping will work!
 
You must log in or register to reply here.
Back
Top