Icky - Progress

Where Alpha builders can post pics and progress etc
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Icky
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Re: Icky - Progress

Post by Icky » Sat Oct 13, 2018 10:08 pm

exxos wrote:
Sat Oct 13, 2018 3:12 pm
:thumbup:

If your running fine, can you copy so files from floppy to hard drive and check HDCS and FDCS on the DMA... Both on scope at same time... So when you see FDCS go low and the high, there will be some delay then you should see HDCS going low.... Its the delay between the 2 which is of interest...
Thanks Exxos. I'll take a look once I have tested the NASTY DMA in my original ST to confirm that it truly is NASTY :)

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Re: Icky - Progress

Post by exxos » Sun Oct 14, 2018 1:21 am

I half wonder if those ste buffers , while they will cure the 1772 bus conflict, if they are also a contributing issue as to why the ste suffers with write issues on the DMA port... Just thinking out load here, but can't help but feel delaying the bus to the DMA by up to 1x 8mhz clock cycle isn't really a good thing to do.

As though before, I think a buffer between the 1772 and DMA would be a better idea, and buffers would isolate the 1772 bus fast, but it wouldn't add delays to the DMA port, which think is a good thing.

There is still the idea to add buffers on the DMA port, but I don't think they are really needed...

I also half wonder if that 1772 conflict is part of some screwy things I saw on the DMA bus ages ago.. As the 001 DMA seemed to act like a open collector output, but it seemed to magic up delays when the bus was loaded more, which suggest a open collector type output, but even so, I never really figured out why the 001 had this odd behaviour. But maybe if the 1772 bus was conflicting with the DMA, that could be part of the confusion as to why the 001 was acting oddly, when the -38 didn't.

I didn't look into it much at the time .. But maybe the 001 checks for all logic hi on the bus before it actually outputs data to the bus. That's the only way I can describe it. It would kinda make sense and tally with the odd results I found. Though with the ste buffers, it shouldn't need that odd 001 "logic". On that basis , the stfm would be the main useage of the 001 not the ste... I don't think I ever saw any 001 DMA in a stfm.. Only later ste....
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.

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Re: Icky - Progress

Post by rpineau » Sun Oct 14, 2018 2:21 am

I like the idea of the buffer to isolate the 1772 to prevent data conflict.
I also like the idea of buffering the DMA port... but without delay on it.
This would protect the DMA chip, make the external DMA data more stable.
If you look a the schematics for some of the Atari hard drive, they do buffer the out port of these with some 74LS245 to the next device.
with /G wired to /HDCS and DIR to R/W , thus not adding delays on the DMA devices (besides the buffer propagation time).
Working ones : MegaSTE (68020) / TT030 / Falcon with AB040 & Eclipse / 1040STF
Need testing : Falcon with CT2

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Re: Icky - Progress

Post by exxos » Sun Oct 14, 2018 2:56 am

Yeah I saw Atari drives have the buffers, again odd that ste have same buffers again... I guess it could explain a little why Atari drives seemed to work better than 3rd party ones back in the day. I guess most issues were with pre-ste machines as I assume 3rd party drives may not have the buffers and could fail to function correctly.

Mostly thoughts are for ultrasatan. Jookie used resistor dividers on the io, so suspect a fair load on the io lines, so buffers would help there. But I don't know how later ones were done.. If they use resistors still or proper level translation chips..

I will probably add DMA buffers just to be sure anyway. Taking load away from the DMA can only be a good thing. And of course buffer to isolate 1772...

Will start a bodge PCB for all this soon. There still shouldn't be any real reason for the DMA port to malfunction how it is now anyway... But known how iffy all this stuff is, I wouldn't be supprised...
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.

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Re: Icky - Progress

Post by Icky » Sun Oct 14, 2018 9:28 am

exxos wrote:
Sun Oct 14, 2018 2:56 am
Yeah I saw Atari drives have the buffers, again odd that ste have same buffers again... I guess it could explain a little why Atari drives seemed to work better than 3rd party ones back in the day. I guess most issues were with pre-ste machines as I assume 3rd party drives may not have the buffers and could fail to function correctly.

Mostly thoughts are for ultrasatan. Jookie used resistor dividers on the io, so suspect a fair load on the io lines, so buffers would help there. But I don't know how later ones were done.. If they use resistors still or proper level translation chips..

I will probably add DMA buffers just to be sure anyway. Taking load away from the DMA can only be a good thing. And of course buffer to isolate 1772...

Will start a bodge PCB for all this soon. There still shouldn't be any real reason for the DMA port to malfunction how it is now anyway... But known how iffy all this stuff is, I wouldn't be supprised...
I also like the idea of buffer on the DMA port and to isolate the 1772. This should help protect the chips as mentioned by rpineau.

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Re: Icky - Progress

Post by Icky » Sun Oct 14, 2018 9:32 am

OK - One more to add to the testing pot.

We have MIDI.

Using Pro24 on the STF Remake to play a simple song (pretty rubbish one at that - probably not the right instrument setup) out of MIDI to my MIDI controller hooked up to GarageBand.



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Re: Icky - Progress

Post by exxos » Sun Oct 14, 2018 11:40 am

:bravo:

Did you test the nasty dma ? Not sure if I missed that post or not.
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.

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Re: Icky - Progress

Post by Icky » Sun Oct 14, 2018 11:56 am

exxos wrote:
Sun Oct 14, 2018 11:40 am
:bravo:

Did you test the nasty dma ? Not sure if I missed that post or not.
No not yet - Juggling a few things around between my DIY jobs I have to do this weekend. Tiling a bathroom or Atari work - hmm

Have just put it into the original but am trying to find all the parts I had stored to bring it up as it was hanging on my wall as art viewtopic.php?f=18&t=700

Will definitely get this test done today

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Re: Icky - Progress

Post by exxos » Sun Oct 14, 2018 11:58 am

Icky wrote:
Sun Oct 14, 2018 11:56 am
No not yet - Juggling a few things around between my DIY jobs I have to do this weekend. Tiling a bathroom or Atari work - hmm
Atari work helps humanity, tiling the bathroom just looks pretty :P

Icky wrote:
Sun Oct 14, 2018 11:56 am
Have just put it into the original but am trying to find all the parts I had stored to bring it up as it was hanging on my wall as art viewtopic.php?f=18&t=700
Yikes! Yeah I remember seeing that before now!
Icky wrote:
Sun Oct 14, 2018 11:56 am
Will definitely get this test done today
:thumbup: My sanity is hanging by a thread with this if that helps :crazy:
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.

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Re: Icky - Progress

Post by Icky » Sun Oct 14, 2018 8:18 pm

exxos wrote:
Sun Oct 14, 2018 11:58 am
Icky wrote:
Sun Oct 14, 2018 11:56 am
No not yet - Juggling a few things around between my DIY jobs I have to do this weekend. Tiling a bathroom or Atari work - hmm
Atari work helps humanity, tiling the bathroom just looks pretty :P

Icky wrote:
Sun Oct 14, 2018 11:56 am
Have just put it into the original but am trying to find all the parts I had stored to bring it up as it was hanging on my wall as art viewtopic.php?f=18&t=700
Yikes! Yeah I remember seeing that before now!
Icky wrote:
Sun Oct 14, 2018 11:56 am
Will definitely get this test done today
:thumbup: My sanity is hanging by a thread with this if that helps :crazy:
Finally got the NASTY DMA in an original ST.

Well floppy boots but the HDD is not recognised.

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