Gotek / A500 compatibility problems

[kokaib]

Originally Posted by solarmon

Your definition of 'work' might not be the same as mine!

The only major component that might be 12V tolerant is the U4 voltage regulator, but the U1 chip is not, and like you said, a USB stick getting 12V will usually fry it unless it has some protection circuit in it.

You could also get 12V feeding back in to the host equipment if the pull up resistors are damaged and are shorted to 12V.

In my definition the "work" is mean the Gotek is loading the games and games are running fine.

We measured the power cable pins the 5V and the 12V are the right pins. The socket is not inversly on the motherboard and neihter on the Gotek..

I will make a photo from the power cable. You will see the cable is the right direction. If the direction should be wrong the floppy drive could not work. The new gotek works properly. It is not kill the usb stick and adf files is not going to corrupt.

[solarmon]

Just to clarify. I'm not suggesting that you may currently have the power connected incorrectly. But if you have in the past at any point have accidently connected incorrectly then it may have caused damage.

[matti46]

Hi

My first post on this forum

I have a problem that fits to earlier description.
I have Amiga 500 (board rev. 6a) + A501 without battery, external floppy adapter, DF0/1-selector and Gotek with FlashFloppy 3.13A. No FF config file but I use HxC-compat mode. Amiga has it's original internal floppydrive. I also have another working A500 (also rev. 6a) for testing purposes.

I have two problems:

First things first. I have problems with most of the games because gotek isn't loading them past the Cracktros. WB 1.3 Loads just fine and also about half of my games. Problems happens when gotek replaces internal drive and when it is connected to external drive adapter. In both cases df-selector is in correct position. I tried Amiga testkit which loads ok. I did the disk test and it told me that I don't have ready signal (in both cases).

Some of the working games:
North & South
Lemmings 2: The Tribes
Walker
Firestrike

Some of the not working games:
Great Giana sisters
Lotus Turbo Challenge II
Turrican
Pinball Dreams
Zool 2

Second problem is with external adapter. Problem happens when I connect two floppy drives to amiga and try to load games from drives. I have diskette of Lotus Turbo Challenge II. It lauches fine from internal drive but not from the external, which is actually internal drive from the other 500 I have. I made little chart to visualize problem. df-selector is adjusted accordingly.

Only external connected No loading past cracktros
Only internal connected Game loads ok
Both connected (using internal) No loading past cracktros
Both connected (using external) No loading past cracktros

I didn't add Gotek to this chart because it didn't load past cracktros in any configuration. I couldn't try Testkit with these drives because I don't have it on diskette. Another thing that may be compilation of issues is with X-Copy. When I tried to copy disk from internal Gotek to External floppy X-Copy told me that I don't have disk in the drive. External drive didn't even try to read. and df-selector was in correct position. Also when I have external adapter connected WB won't react to disk change in any of the drives.

Could reason here be the missing ready signal and what can I do about it. I tried latest method in this thread and it didn't work. I have also another Gotek coming for testing, but it doesn't explane the problem when using only disk drives. And I already tried another external adapter, CIA chip and df-selector. And everything again with my another 500. So I feel kind a lost with this. Any ideas?

[demolition]

'No loading past cracktros' is indicative of a missing ready signal which is also what the test kit says. Since the drive selector should not interfere with the RDY signal, my guess is that the source of the problem is the external drive adapter. Perhaps is it permanently asserting the RDY signal which will override the signal from all other drives as well. Which adapter do you have?

[matti46]

I have Voultar LLC Amiga HDD interface V1.0.
I think its this one: https://oshpark.com/shared_projects/ymdOTnh6
I haven't soldered it. And I got another one from seller for testing. He told me that the problem could be that I try to use internal drive as external drive without modding. I have to do modding to the internal drive if I want to use it as external drive. I think I'm not going to mod actual Amiga drive but more likely some old PC-floppy drive.

[demolition]

If the adapter is made for drives with PC interface then that would explain why RDY is not working. Amiga uses pin 34 for RDY while on PC drives this is DSKCHG. On the Gotek this is an easy change that does not require modding, but you'll have to change its settings as it defaults to an Amiga interface when loading Amiga images (I know that HxC does this so I assume FF does as well). If you have the OLED display on the Gotek you can change it directly in the menus, otherwise it is probably easier to create the config-file on the PC.

[matti46]

Update. I got new Gotek yesterday. I put the same Flashfloppy in it than before. It still has the same problem. Now I tell fact about the external adapter. It has two modes. Amiga disk mode and PC disk mode. I'm not sure what is the actual difference between these modes. I think it could be something with RDY signal maybe. When I use gotek as an external drive with the adaptor and use the adaptor in Amiga disk mode it doesn't load game after cracktros. Anyway, if I'm trying the same thing with the adaptor in PC-disk mode it will do mostly the same thing. BUT I can continue loading if I "reinsert" the ADF image by pressing gotek button up and down in sequence to select next image temporarily and then back to correct image. Depending on the game, some of them will load to the next "stop". Others load only half a second and then I have to repeat image reinserting process. I managed to load Giana sister this way but I had to do reinsertin 10-20 times. It feels like it ejects the disk from drive for some reason.

And now I have swapped all the parts. I start to think could this be compatibility issue or are ADF images bad or something. On the other hand, same images load just fine if they are on the diskette and in the internal drive. Strangely even the new gotek wont load these problematic games if it is as internal drive.

Does anyone have experience with these Voultar LLC FFD adaptors? Any idea what could be the better solution if this is a compatibility thing? And I'm still troubled by this "gotek not working as an internal disk drive" issue.

[demolition]

The adapter should be in Amiga disk mode no matter if using it with the Gotek or the floppy drive. It sounds to me like either the external floppy adapter is faulty or the connecting ribbon cable.
Your 'reinsertion' method will toggle the DSKCHG (disk change) signal which on Amiga drives (like your FF Gotek) is present on pin 2. On PC drives though, pin 2 is used for density select. When your adapter is set to PC mode, it should ignore the density select signal but it seems like it may be passing this on as the RDY signal. If this is the case, then either it is not configured correctly, or something is messed up with the design.

[matti46]

I just want to forget the external adapter for now and get the Gotek working as an internal drive. That way I can bypass problems possibly caused by the external adapter. Right now Gotek has the same problem than it had as an external drive. It loads WB and somegames. Still many games get stuck after crackatro. List of the working/non working games is same as in my first post. This is the second gotek right now. I have one still coming but that is for another project. If ready signal is the problem is there anyway to fix it?

Stephen Kitt mentioned next at Stack Exchange retrocomputing page when talking about RDY signal:

"You’ll need it if you want to use the drive in some other systems (notably the Amiga, the Amstrad CPC and PCW). It must be active low when a disk is in the drive, and importantly, it must switch to high and back when the disk is replaced."

Is there anyway I can measure this by a multimeter or is this something that has to be measured with an oscilloscope? Which I don't have :/

[demolition]

If the FF settings are set to defaults, it will use an Amiga interface when loading Amiga images, with the RDY signal in the proper place. Since you probably didn't change the FF settings and have tried two different Goteks, I doubt your problem is with the Gotek. Have you tried another floppy cable?

[matti46]

Actually I have. And all cables work fine with normal internal disk drive. And I have tried this with two different Amiga 500.

[solarmon]

First you need to rule out the ADF files. I would set up WinUAE to emulate your A500 setup and prove the ADF files load OK.

[lesta_smsc]

Also make sure USB stick is not the issue. I had one which would write but when I checked hash of files they were wrong. USB stick swapped for another and it worker fine.

[matti46]

I tested the adf files. They were okay. I used them directly from usb stick in WinUAE. I also tried several USB-sticks. Actually one that I have been using worked the best. There was also one other that worked.

There is one possible HW issue with that external adapter but I can't tell more about it right now. I will when I have something solid to tell.

[matti46]

Okay. Problem is solved now. There was actual hardware design issue with the external adapter's board which led to direct contact of 5v line from the Amiga and ready signal line. Amiga survived from this, but it turns out Goteks not. Direct 5v burned couple of mosfets from the both of my Goteks. Guy how I bought this adapter from found this issue and fixed the board for me. He also send me couple new mosfets and I got my Goteks fixed. If anyone is coming across the same issue with this same type of board check what is happening around 12k resistor.

https://drive.google.com/file/d/1IjO...ew?usp=sharing

I hope this to be fixed in future revisions of the board.

[matti46]

And thanks to every one for help, support and troubleshooting ideas!