Idea for new project... simple DD1 Floppy controller......

[pocoaust]

Hi mate,

Love your work, have built the backplane and ROM board. No issues just an idea

Have you considered a simple DD1 Floppy interface replacement. They are getting very hard to find. The rom could go on the ROM board, and a small addon board could carry the fdd controller and support logic on your bus expansion.

I have attached the DDI schematic, could you give me your thoughts on this.

Best Regards
Paul

[revaldinho]

Thanks for your comments.

It's a good idea. I mean, there are plenty of SD card alternatives to the DDI-1 around for the 464/664 but I think that only Zaxon's DDI-3/4/5 boards provide physical drive interfaces. I actually do have a DDI-3 and it works very well, also with a Gotek as Drive B on the expansion connector.

Deleting the ROM and control circuitry is definitely the thing to do. I would like to keep any board smaller than 80x100mm to fit the freeware- Eagle license (100x100mm is also the limit for the cheap proto-packs from Seed). This would probably fit without the ROM.

I'll think about it. I have a couple of other projects in progress at the moment, so it may take a while to get to this and although I don't really need one myself, I agree that it would be worth making a clone more generally available.

[pocoaust]

That's great. I am just a novice teaching myself in retirement, but am happy to pay for test boards and have plenty of 765 ic etc which I could send you. Anyway let me know if there is anything I can do on my side and please keep me in the loop. Thanks Paul in australia. Take care...

…

On Sat, 26 Nov 2022, 9:26 am revaldinho, ***@***.***> wrote: Thanks for your comments. It's a good idea. I mean, there are plenty of SD card alternatives to the DDI-1 around for the 464/664 but I think that only Zaxon's DDI-3/4/5 boards provide physical drive interfaces. I actually do have a DDI-3 and it works very well, also with a Gotek as Drive B on the expansion connector. Deleting the ROM and control circuitry is definitely the thing to do. I would like to keep any board smaller than 80x100mm to fit the freeware- Eagle license (100x100mm is also the limit for the cheap proto-packs from Seed). This would probably fit without the ROM. I'll think about it. I have a couple of other projects in progress at the moment, so it may take a while to get to this and although I don't really need one myself, I agree that it would be worth making a clone more generally available. — Reply to this email directly, view it on GitHub <#12 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AVKNH4OUZUWGPEVKP7TZCOLWKE4IFANCNFSM6AAAAAASJ2BUQA> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[pocoaust]

Just an after thought, 3.5" style connector so you could support gotek as mentioned would be ideal. Take care. Paul;-)

…

On Sat, 26 Nov 2022, 9:55 am Paul O'Connor, ***@***.***> wrote: That's great. I am just a novice teaching myself in retirement, but am happy to pay for test boards and have plenty of 765 ic etc which I could send you. Anyway let me know if there is anything I can do on my side and please keep me in the loop. Thanks Paul in australia. Take care... On Sat, 26 Nov 2022, 9:26 am revaldinho, ***@***.***> wrote: > Thanks for your comments. > > It's a good idea. I mean, there are plenty of SD card alternatives to the > DDI-1 around for the 464/664 but I think that only Zaxon's DDI-3/4/5 boards > provide physical drive interfaces. I actually do have a DDI-3 and it works > very well, also with a Gotek as Drive B on the expansion connector. > > Deleting the ROM and control circuitry is definitely the thing to do. I > would like to keep any board smaller than 80x100mm to fit the freeware- > Eagle license (100x100mm is also the limit for the cheap proto-packs from > Seed). This would probably fit without the ROM. > > I'll think about it. I have a couple of other projects in progress at the > moment, so it may take a while to get to this and although I don't really > need one myself, I agree that it would be worth making a clone more > generally available. > > — > Reply to this email directly, view it on GitHub > <#12 (comment)>, > or unsubscribe > <https://github.com/notifications/unsubscribe-auth/AVKNH4OUZUWGPEVKP7TZCOLWKE4IFANCNFSM6AAAAAASJ2BUQA> > . > You are receiving this because you authored the thread.Message ID: > ***@***.***> >

[pocoaust]

Tried to send this to you but github said was 2 large. Here is link.... https://www.grimware.org/lib/exe/fetch.php/documentations/hardware/amstrad.cpc/manuals/service.manual.ddi-1.fd-1.pdf Let me know if You need anything else. Take care Paul

[grafzahl12345]

Hi revald,
are you also still useing eagle and is there enough space in the cpld for a second adress select logic? So i'm intrested too, you can cut me in if you like.

[revaldinho]

Yes, for these projects at least I'm still using the netlister.py/freeware Eagle PCB tools.

For a DDI-1 clone without a ROM and the associated decoding I don't think there will be any need for a CPLD. It may be possible to reduce the chip count by refactoring what's left with the ROM logic gone, so I think that it should all fit the in the 80x100mm constraint without any need to go for a CPLD.