Next Gotek on CPC464 with DDI-1 and FD1 issue

[SerErris]

Hi,

I do have now a lot things to play around. Beneath having the said DDI-1 and the FD-1 I also have the Vortex X-Modul and a Gotek.

If I connect the Gotek to the DDI-1, it does not work as expected. The FD-1 cannot read anymore (read errors).

If I connect it to the X-Module (which has the DDI-1 inside) then I can either read the Gotek, or the DDI-1 depending on which was powered on first. 

So I think something is not correct with the cable. I do not want to sacrifice my nice DDI-1 cable, so anything I need to remove from the gotek cable, so that it can work?

BTW: the new gotecs with the SFRKC30.AT4.35 come with FF installed and also have the MOT line connected. That is awesome as now the readyproblem goes away. I got it working in both 3" emulation, as well as in 3.5" emulation. 

I could read the vortex format disk as well as normal CPC 3" disks.

So far so good. But I could not figure out what I need to do to be able to use both at the same time.

BTW: Jumper settings are MOT and S1 on the Gotek. That should be the correct configuration for Drive B. 

So any idea where I can figure out on what to do?

[Audronic]

@SerErris 

Try removing the MOT link.
I use these Goteks and they work well
PS:- I have a rotary encoder to allow me to eject disks for CPM

Good luck

Keep Safe

Ray

[SerErris]

Hmm .. okay will try that.

[SerErris]

No success ...

I have created a custom FF.cfg file (please find attached) and I am running on FF 4.6a:

I think the most important parts are those from the config file:

interface = shugart
host = unspecified
pin02 = high    (this is actually Pin33 on DDI-1 (or any CPC) as per https://www.cpcwiki.eu/index.php/DIY:Floppy_Drives)
pin34 = rdy     (this is Pin1)

I also have set those, they work in general pretty good:
track-change = realtime
write-drain = realtime
index-suppression = yes (not sure what would be correct here)
head-settle-ms = 12 (default)
motor-delay = 200
chgrst = step  (is this correct?) (default)


The rest of the settings are just display, rotary and other behaviour selection of the gotek itself.

What I read from the service manual of the DDI-1 and also from this post here is that the FD-1 sends 5 volts to power the DDI-1 and that the Gotek does not expect this.

So that should be PIN 2,4,6 and 14 of the Gotek floppy connector. 

Looking at the standard 5,25 floppy connector, that should not actually be an issue, because all lines are normal signal lines and having them at 5V does not harm. The GOTEK will just ignore them (and they are not used in the CPC). 

2: Spare
4: Spare
6: Drive Select 4 (not used in CPC)
14: Drive Select 3 (not used and high means - not selected anyhow as any signal is low level = active)



So I do think it is not the electrical connection at all. That should work.

I try to describe my procedure and the error I do get:
1. I power on FD-1
2. Then I power on the Gotek
3. Then I power on the CPC (this is in accordance to the Vortex F1-X manual.
4. Then the system starts and tries to do the turnkey autostart (check if a "HELLO.BAS" is available and runs it).
5. You can then hear the FD-1 motor starting, and the had going forward and backward all the tracks and then doing this 4 times "track step" noise (drk, drk, drk drk), This repeats two time and then the VDOS gives up and goes to READY prompt.
6. I am then running CAT command and the same thing happen as in 5. In addition I get the german message of VDOS "Laufwerk A: Lesefehler - Wiederholen J/N ?"

If I switch to drive B (Gotek) and try the same cat command I do get the correct out put (vortex format disk as you can see).

You cannot view this attachment.

Now comes the part where I am really scratching my head:

If I remove the USB stick from the Gotek. Drive A (FD-1) works as normal.

So I am not sure in what way Gotek interferes with Drive A and what in my configuration fail could make that happen.

Any idea? Or is this a firmware issue?

Can anyone send me their FF.cfg that is currently working for them?

[SerErris]

Some more research to pinpoint the issue and take more and more components out of the equation:

1. DDI-1 only (no VDOS anymore - just AMSDOS).

The result stays excatly the same with an AMSDOS formatted disk in FD-1 and an AMSDOS formatted disk in Gotek.

AMSDOS=A, Gotek=B.

Still the FD-1 does the same noise. (seeking all tracks forward and backward, then trying to get to track0 or something).

I recorded the noise for you, so that you can better understand what it does.

[SerErris]

Okay, I have found the issue...

DO NOT USE GOTEK SFRKC30.AT4.35

I did have another Gotek lying around an SFRC922D

using the same firmware (3.37) on both with the exact same settings (actually no FF.cfg at all), worked like a charm with the 992D but did create the issues on the AT4.35. 

I try to get in contact with the flashfloppy author, but those new Goteks are currently not working with neither 6128 nor 464+DDI-1+FD1.

However it is working if it is the single drive. So if you mod your DDI-1 to get powered by the CPC, then the gotek will work as you single disk drive.

[SerErris]

Okay, 

confirmed by keirf. It is a bug. After the 435 gotek has been selected it wont let go the RDATA line. And therefore it pollutes the bus and create the read errors.

Now hopefully as we found it - we can hope for a fix in the firmware :-)

[SerErris]

Okay fix is there in 3.38

[SerErris]

Okay, I need to get this very old thread back out of the attic.

Anyone has this configuration:

CPC464 + DDI-1 + DF1 as drive A: and a Gotek as drive B?

I cannot get it to work, whatever I do.

Gotek works as external drive B on the 6128 with a special cable.
https://www.cpcstore.co.uk/product/floppy-cable-deluxe-/9?cp=true&sa=false&sbp=false&q=false&category_id=4

So the cable alows me to exchange the drives. However that is in my opinion not even needed.

What I tried:
I do have the normal DDI-1 with the build in cable and I attached it to the DF-1. That works totally normal.

Then I bought an extension cable with a male connector and a femalconnector, that is just a straight cable.

I then connected the Gotek with that cable to the second port.

I had it running with a X-Module from Vortex at some point in time, but I cannot get it running anymore.

I am pretty sure nothing is right anymore - e.g. wrong jumper settings and everything.

So can anyone that got this working let me know how exactly this configuration works?

Thanks

[SerErris]

Okay, I recreated the schematic for the Cable as the version in the DDI-1 Service Manual is really confusing and in bad quality.
I did some measurements and here is my quick schematics of the DDI-1 Cable and the connectors.
You cannot view this attachment.

So it looks like there should be no issue whatsoever to connect a Gotek to Drive B connector, as it is absolutely correct.

Also the correct setting for Pin 2 and 34 should be NC and READY.
Jumper needs to go to S1 and not S0.

And that should actually fix it. The Motor line also can be enabled if existent.

So with all that setup I still wonder what goes wrong, but can only test further in the next few days.

Any ideas?

[Richard_Lloyd]

Your schematic looks correct but I number everything the other way round 

My 464 has a 3" drive and a Gotek as drive A and another 3" drive and Gotek as drive B. I have a switch to send DS0 to either the 3" drive or the Gotek and another switch to do the same for DS1 and it all works.

However, I have a switch to permanently connect pin 34 to 33 to keep the READY constantly on.  (Pins 1 and 2 on your schematic). Other than this I think your scheme should work.

Good luck.

[SerErris]

Actually, the Pin 33/34 connection was the main difference for my external 6128 cable.

But it should not be required for a gotek, as it handles Ready signal correctly.

I now put everything to my logic analyzer and I can see Ready line working correctly.

Also now I removed the X-Module from the equation and it works for now.

It might be the case, that the X-Module expects a 720k disk ... and not the 180k 3" disk format.

For now I just needed to threaten it with a logic analyzer and it behaves. I am sure, as soon as I remove it - it will stop working :-D

[SerErris]

Okay, here is what the issue is:

With the X-Module, the CPC can work with 2 sided drives. That means that the side pin has relevance and is getting used (where with AMSDOS is always high).

However this line looks jittery on one of the controllers I have.

I need to look at it with an oscilloscope, but I just think, the line is floating instead if low. High is not a problem, but low will not work.

So all mysteries clarified so far and GOTEK is working just fine.