ST314 drive replacement.

Atari talk, or the life and the universe and things. Just keep it clean!
stephen_usher
Posts: 377
Joined: Mon Nov 13, 2017 7:19 pm
Location: Oxford, UK.
Contact:

Re: ST314 drive replacement.

Post by stephen_usher » Sun Oct 06, 2019 5:13 pm

OK, moved the Motor-On line over to line 16 on the ribbon cable and now the internal drive stops working.
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.

stephen_usher
Posts: 377
Joined: Mon Nov 13, 2017 7:19 pm
Location: Oxford, UK.
Contact:

Re: ST314 drive replacement.

Post by stephen_usher » Sun Oct 06, 2019 5:52 pm

I've moved Motor On back to pin 10. Without it connected the drive isn't recognised at all.

From what I can see on the oscilloscope it's acting normally.

When the drive is accessed the activity light comes on, it seeks but the motor isn't running.

There's definitely 12V getting to it and another Atari drive (the old 720K drive originally in the TT) behaves the same way.

There's obviously something missing.
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.

stephen_usher
Posts: 377
Joined: Mon Nov 13, 2017 7:19 pm
Location: Oxford, UK.
Contact:

Re: ST314 drive replacement.

Post by stephen_usher » Sun Oct 06, 2019 6:04 pm

Could it be possible that I need to wire all the odd-numbered wires to ground in case the motor ground isn't connected? I doubt it as that should be using the power input ground rather than data ground.
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.

stephen_usher
Posts: 377
Joined: Mon Nov 13, 2017 7:19 pm
Location: Oxford, UK.
Contact:

Re: ST314 drive replacement.

Post by stephen_usher » Sun Oct 06, 2019 7:07 pm

That's interesting... I put a Flashfloppy-ed GoTek on in place of the floppy.

Strangely it thinks it's the internal drive and drive B at the same time (unlike the real floppy drive). You can access it fine as drive B, both reading and writing.

I think the drive access is a bug in Flashfloppy in that it's seeing the Atari drive strobe and thinking that it's selected continuously.

So, if I could get the drive motor to operate I think it will all work. From what I can see the "Motor On" signal is active low. That's what the 'scope's saying anyway.
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.

stephen_usher
Posts: 377
Joined: Mon Nov 13, 2017 7:19 pm
Location: Oxford, UK.
Contact:

Re: ST314 drive replacement.

Post by stephen_usher » Sun Oct 06, 2019 7:39 pm

OK. I now have the interface working! Swapping both the motor on and drive select lines to the PC version worked... on another floppy drive and the GoTek.

However, the drive sent by Best Electronics and "guaranteed working" can't read floppies. Gah!

I can try stripping the drive from the older of the two STFMs I have in the loft which has a long slot floppy and try that. The machine's developed a memory fault anyway so either needs a rebuild or used for spares.
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.

stephen_usher
Posts: 377
Joined: Mon Nov 13, 2017 7:19 pm
Location: Oxford, UK.
Contact:

Re: ST314 drive replacement.

Post by stephen_usher » Mon Oct 07, 2019 7:05 pm

I've discovered why the TDK isn't working... the upper head has become unstuck from the mounting frame during transit. I was wondering what was rattling about inside and then saw the head dangling when I took the top off. Well that was an expensive bit of junk... $99 + shipping + duty.

I'm now retro-fitting the red optic onto the Chinon drive from my spare/not working currently STFM. I'm going to have to change the LED as it's green and I need red. I can hoik the LED out of the dead drive for that.
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.

stephen_usher
Posts: 377
Joined: Mon Nov 13, 2017 7:19 pm
Location: Oxford, UK.
Contact:

Re: ST314 drive replacement.

Post by stephen_usher » Mon Oct 07, 2019 8:36 pm

At last! Having moved the red light channel over to yet another fascia and swapped the green LED with the red one from the dead TDK drive I now have a fully operational and authentic looking SF314 drive. Phew!
IMG_1617.JPG
IMG_1617.JPG (90.08 KiB) Viewed 366 times
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.

User avatar
exxos
Site Admin
Site Admin
Posts: 8486
Joined: Wed Aug 16, 2017 11:19 pm
Location: UK
Contact:

Re: ST314 drive replacement.

Post by exxos » Mon Oct 07, 2019 10:08 pm

:bravo:

Not giving up has it rewards :thumbup:
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxoshost.co.uk/atari/last/storenew/ - All my hardware mods for sale - Please help support by making a purchase.

stephen_usher
Posts: 377
Joined: Mon Nov 13, 2017 7:19 pm
Location: Oxford, UK.
Contact:

Re: ST314 drive replacement.

Post by stephen_usher » Mon Oct 07, 2019 10:55 pm

The result... my original ST system fully renovated and happy! :D
renovated-st.jpg
renovated-st.jpg (150.18 KiB) Viewed 349 times
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.

tzok
Posts: 150
Joined: Sat Dec 30, 2017 2:27 pm

Re: ST314 drive replacement.

Post by tzok » Tue Oct 08, 2019 11:18 am

Motor ON is common for all floppies, and regardless which one is selected, motor starts in all, this is normal behavior.

In the standard SF314, the DS1 line from Atari STf is connected to the DS0 pin in the drive, so the drive itself has to be set for DRIVE0. In short ST, there are both lines present on FDD connector, and they are crossed in FDD conector of the floppy drive, so first in chain is DS0, and second is DS1, but internally both have to be set as DRIVE0, same is for Gotek (by default it is set as DRIVE1).

Post Reply

Return to “CHAT FORUM”