Gotek as an 8" drive replacement

HxC Floppy emulator support for all others computers...
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namachari
Posts: 40
Joined: Tue Aug 23, 2016 11:33 am

Gotek as an 8" drive replacement

Post by namachari » Tue Aug 30, 2016 6:34 am

Hi all,
I’ve been lurking for a while, but finally decide to register and ask a few questions.

I would like to emulate the 8” drives on the following systems:
- 1976 Processor Technology SOL-20 with Disk Jockey 2D controller board connected to dual 8” drive (DSDD), running CP/M 2.2
- 1976 IMSAI 8080 with Versafloppy 1 controller connected to dual 8” sugart drives (SSSD), running CP/M 2.2 & 1.4

Being a little strapped for cash, I was thinking to use the cheap Gotek drives flashed with the HxC firmware, and adapt the 8” 50 pin cable to a 34 pin cable using a 50to34 adaptor:

https://github.com/NF6X/fd50to34

I have already been able to make backup files from both systems using a borrowed Kryoflux and the help of the Kryoflux forums folks.

Before I go ahead and purchase the drives and parts, I was wondering if anyone has had any experience using the Gotek as an 8” drive replacement?

Thanks in advance

Phil

namachari
Posts: 40
Joined: Tue Aug 23, 2016 11:33 am

Re: Gotek as an 8" drive replacement

Post by namachari » Wed Aug 31, 2016 6:31 am

Well, I bit the bullet and went ahead and ordered a Gotek, firmware programer, and a 2x16 LCD display etc.

Hope I can get it all working.

Philip

namachari
Posts: 40
Joined: Tue Aug 23, 2016 11:33 am

Re: Gotek as an 8" drive replacement

Post by namachari » Wed Sep 14, 2016 11:27 am

All the parts finally arrived.
Flashed the Gotek drive with the HxC boot loader, hooked it all up the the IMSAI 8080. Converted some of my .IMD files (made using a Kryoflux) to the HxC format using the HxC software...

It booted CP/M 2.2 first time!
Boots CP/M 1.4 also.
Runs Mbasic perfectly.
Haven't tried writing anything yet...It's getting late so I'll do more testing tomorrow.

Great stuff!

Philip

Martin Hepperle
Posts: 24
Joined: Fri Sep 09, 2016 11:20 am
Location: Germany

Re: Gotek as an 8" drive replacement

Post by Martin Hepperle » Thu Sep 15, 2016 11:46 am

sounds great ... when everything works, can you provide some sketches/photographs about the connections and switch settings as a guideline for other people with similar "problems"?

I am interested in replacing Tandon-TM-100-2A 5.25" disk drives.

Thank you,
Martin

namachari
Posts: 40
Joined: Tue Aug 23, 2016 11:33 am

Re: Gotek as an 8" drive replacement

Post by namachari » Sat Sep 17, 2016 9:51 pm

Hi,
I did say to worked first time, but that doesn't mean that sorting it all out was easy...or quick.

Here were my steps.

- Built a custom cable to connect to my 8" drive.
- Purchased a FDADP from dbit: http://www.dbit.com/fdadap.html
- Borrowed a kryoflux and using it in conjunction with the FDADP and custom cable, I dumped all my 8" CP/M floppies.
- These raw streams were converted to .imd images
- .imd images were then converted to HFE format using the HxC software
- Purchased a Gotek drive (and serial flashing hardware), soldered on some header pins and flashed it with the HxC boot loader
- Purchased a fd50to34 bare board and built it up: https://oshpark.com/shared_projects/Hr1FTWxB
- Built another custom cable from my 8" drive to the fd50to34
- Connected the gotek to the fd50to34 then to the IMSAI 8080's floppy controller (Versafloppy 1 card)
- Put all appropriate files on USB stick and put that into the gotek
- I had to swap one jumper on the gotek. S1 to S0
- Powered everything up.
- Worked!

namachari
Posts: 40
Joined: Tue Aug 23, 2016 11:33 am

Re: Gotek as an 8" drive replacement

Post by namachari » Fri Mar 31, 2017 1:36 am

I wanted to follow up on this thread.
I now have 3 Gotek/HxC drives.
One is used with an S100 IMSAI 8080 with versa floppy card.
Another is used on a S100 SD systems setup that I recently built from a stack of spare boards. It uses a Versafloppy II card.
Both systems are very similar, and the SSSD disk images used can boot on either system.

I have another HxC/Gotek attached to my S100 SOL-20 with Disk Jockey 2D disk controller. It uses DSDD disk images.

Now the SOL-20 seems to work perfectly, reading and writing to CP/M. Have yet to find an issue.
However both the SD system and the IMSAI can boot and run CP/M and run programs from CP/M, but fail to write.
I have noticed that the disk light will come on and off with the SOL-20 as it accesses the virtual drive, but the SD system the light comes on, and stays on. Not sure why this is. It may be a fundamental difference between the way disk controllers work.

Still haven't been able to figure out what the problem is. It's frustrating.

Phil

IRJustman
Posts: 5
Joined: Tue Apr 25, 2017 1:09 pm

Re: Gotek as an 8" drive replacement

Post by IRJustman » Sat Apr 29, 2017 10:05 pm

Since we're talking about Shugart 8" floppies, I noticed that folks have gotten these to work with a Ferguson Big Board. Was it on an 8" controller connection, or was it in lieu of a 5 1/4" drive? The one I got, I received a lot of 8" floppies with it.

I also have a later CompuPro (Viasyn) box. It came with a 5 1/4" drive, though it can be used with 8" drives as well. I'm considering getting this one going as well.

Does anything special have to be done with the floppy emulators other than using custom cabling/adapters to connect a "5 1/4" drive to an 8" controller? I had to jumper a QumeTrak drive I got with a different CompuPro differently in order to use it with a PC's floppy controller.

namachari
Posts: 40
Joined: Tue Aug 23, 2016 11:33 am

Re: Gotek as an 8" drive replacement

Post by namachari » Mon May 08, 2017 10:22 am

These are with 8" controllers.
Versafloppy 1, Versafloppy 2 (this can also do 5.25, but I'm using it as an 8" controller), and DJ2D controller boards. Please note that I have issues writing with both the Versafloppy controllers.

No, nothing special needed to be done with the Goteks.

Good luck

IRJustman
Posts: 5
Joined: Tue Apr 25, 2017 1:09 pm

Re: Gotek as an 8" drive replacement

Post by IRJustman » Wed May 31, 2017 9:04 am

Nice. That means the only thing I need to do now is get more money so I can get more Goteks and licenses to flash them with new bootloaders. I have already purchased a set of three 8-to-5 adapter boards from OSH Park; I just need the additional parts to finish them up.

--IJ.

davidestewart
Posts: 7
Joined: Fri Oct 27, 2017 10:56 pm

Re: Gotek as an 8" drive replacement

Post by davidestewart » Fri Oct 27, 2017 11:18 pm

Hello,
I am trying to get a very similar setup running using the gotek. I have a compupro 8/16 chassis with a 286 CPU and a disk 1a controller. I have been able to successfully flash a gotek (tested in my kaypro2x). I also have assembled one of those 34 to 50 adapters mention in this thread. Im pretty sure it works as it was tested with a friends siemens 8" FDD.

At this point I have the gotek connected to my disk 1A on the 8" controller. I have the the disk 1A set to boot from the floppies. The one jumper on the gotek is set to D0.


I have tried every bootable compupro image I can find on the web for cdos and CP/M with no results. The images I have tried I suspect are all for 8086 hardware and I think I need an image that has been compupro sysgened with the right loader for the 286.

Any suggestions would be a big help.

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