Atmos/Microdisk - ghost in the machine!?!?!?

If you want to ask questions about how the machine works, peculiar details, the differences between models, here it is !
How to program the oric hardware (VIA, FDC, ...) is also welcome.
omelette
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Re: Atmos/Microdisk - ghost in the machine!?!?!?

Post by omelette »

Chema wrote:
Thu Dec 05, 2019 9:02 am
Glad you fixed that Microdisc!

By the way, do you have any means of writing 3" disks from disk images (dsk)? I know there is a way of connecting a 3" unit to a PC, but it seems nobody has such a setup nowadays.
Thanks. I'm fairly sure the way I did it in the past was using my Atari falcon, which reads PC-formatted disks, although it's almost certainly my Atari ST I use to write the disk image, as I've got a cable to attach an external floppy for that. It's ages since I did it - whenever Sedoric 3 was made available - so details are hazy. I might fire it up and see what I did. I do know that I managed to get Sedoric 3 onto a 3" anyway!

Never knew that double-sided 3" disks were produced, both of mine are SS.

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iss
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Re: Atmos/Microdisk - ghost in the machine!?!?!?

Post by iss »

Chema wrote:
Thu Dec 05, 2019 2:49 pm
Yeah, this seems to get more and more difficult as time goes by :(

Well, no way of making a copy of Blake's 7 or any demo disk created with FloppyBuilder, as they don't have any DOS format. Maybe it is time to start thinking again on a low-level diskcopy tool. I am quite sure we discussed that some time ago.

I really wanted someone to test the game on a double-sided 3" disk drive. Did I ever mentioned that the Jasmin compatible boot loader, which worked perfectly under emulation, completely failed on real hardware? But it took almost a year to find someone with the equipment to test. And there is no way to debug that, unless I steal the unit from the owner :lol:
The 3" drives/diskettes are looking somehow beautiful for me and I'll not retire them soon, and I always enjoy the sound they make :).

About the low-level copy program - my CopyPlus can do it! It's unfinished because I wish to integrate formatting functionality too which was difficult to debug ... 'til 10 day ago when @christian (aka assinie) committed read/write track implementation for Oricutron(!) - it works well so I can finish the copy program (relatively) soon.

And the "crème de la crème" - I have working read sector routine for Jasmin and Microdisc 8) ready to be integrated in FloppyBuilder, once it's done writing should be easier...

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Symoon
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Re: Atmos/Microdisk - ghost in the machine!?!?!?

Post by Symoon »

iss wrote:
Thu Dec 05, 2019 10:43 pm
About the low-level copy program - my CopyPlus can do it! It's unfinished because I wish to integrate formatting functionality too which was difficult to debug ... 'til 10 day ago when @christian (aka assinie) committed read/write track implementation for Oricutron(!) - it works well so I can finish the copy program (relatively) soon.
Don't forget what we discussed earlier: track reading is bugged on real hardware. It will work fine with emulators but send you random bytes with hardware, inserted or replacing existing data.
That's why the 100% PC version was sexy: using another FDC which was not bugged. It worked fine for a while, but here again, I had painful experiences in the past few years: hardware tends to become faulty.

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Chema
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Re: Atmos/Microdisk - ghost in the machine!?!?!?

Post by Chema »

iss wrote:
Thu Dec 05, 2019 10:43 pm
And the "crème de la crème" - I have working read sector routine for Jasmin and Microdisc 8) ready to be integrated in FloppyBuilder, once it's done writing should be easier...
Oh, that is interesting. I am eager to see the difference with the ones used in Blake's7, as they worked in Jasmin and Mictodisc too, but only on emulators. I remember you sent me a dsk for my friend to test in its Jasmin, and it also failed to boot, by the way.

So I am intrigued about the difference in real hardware.

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Re: Atmos/Microdisk - ghost in the machine!?!?!?

Post by Dbug »

One important thing to remember is that 3" floppies have max 42 tracks, if you want to make a 3" version of Blake's, Space 1999, or the demos, they should be regenerated to use 4x tracks, not 8x, else the drive will really not like it.

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Re: Atmos/Microdisk - ghost in the machine!?!?!?

Post by Steve M »

Some documents that might be useful
power s mod001.jpg
power s mod001.jpg (801.66 KiB) Viewed 3464 times
power s mod002.jpg
power s mod002.jpg (751.66 KiB) Viewed 3464 times
power s mod003.jpg
power s mod003.jpg (473.29 KiB) Viewed 3464 times

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Steve M
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Re: Atmos/Microdisk - ghost in the machine!?!?!?

Post by Steve M »

power s mod004.jpg
power s mod004.jpg (662.03 KiB) Viewed 3398 times
Last edited by Steve M on Wed Dec 11, 2019 9:42 pm, edited 2 times in total.

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mikeb
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Re: Atmos/Microdisk - ghost in the machine!?!?!?

Post by mikeb »

Steve M wrote:
Sat Dec 07, 2019 7:03 pm
power s mod004.jpg
This one didn't work (forum bug) -- I hope nothing important is on page 4 ;)

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Steve M
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Re: Atmos/Microdisk - ghost in the machine!?!?!?

Post by Steve M »

Fixed, I hope.

There's another version of this modification which fits a 74LS125 in the IC11 space. I left that version as it stops the Oric working without the disk drive IIRC.
I have an external add-on that fits a chip between the expansion port and the disk interface leaving the Oric intact.
(I think it's the same 125 chip, but I'll need to check. )

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Chema
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Re: Atmos/Microdisk - ghost in the machine!?!?!?

Post by Chema »

Steve M wrote:
Sat Dec 07, 2019 7:03 pm
power s mod004.jpg
Has anybody done this and confirmed it works to avoid problems with external peripherals?

This is the first time I see this mod....

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Re: Atmos/Microdisk - ghost in the machine!?!?!?

Post by NightBird »

Hi

Remember you have also this mod to improve Phi2, in compatibility with ROM/EPROMs: please read CEO-MAG no 288, april 2014, pp. 8-13.

Enjoy! :D

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Steve M
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Re: Atmos/Microdisk - ghost in the machine!?!?!?

Post by Steve M »

Chema wrote:
Tue Dec 10, 2019 9:52 am

Has anybody done this and confirmed it works to avoid problems with external peripherals?

This is the first time I see this mod....
The power supply mod works. I'm not sure how altering the Oric works with other things. The mod I have is with the 125 chip and that Oric wouldn't work on its own, last time I tried it - it needed to be connected to the disk drive.(I'm not sure if that makes sense?)

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Steve M
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Re: Atmos/Microdisk - ghost in the machine!?!?!?

Post by Steve M »

Here's the other version.
I would focus on the power supply mod and use an alternative to improve data lines.
timing mod001.jpg
timing mod001.jpg (1.36 MiB) Viewed 3336 times
timing mod002.jpg
timing mod002.jpg (1.14 MiB) Viewed 3336 times
timing mod003.jpg
timing mod003.jpg (1.17 MiB) Viewed 3336 times

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Steve M
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Re: Atmos/Microdisk - ghost in the machine!?!?!?

Post by Steve M »

timing mod004.jpg
timing mod004.jpg (1.31 MiB) Viewed 3336 times
timing mod005.jpg
timing mod005.jpg (1.28 MiB) Viewed 3336 times
timing mod006.jpg
timing mod006.jpg (1.03 MiB) Viewed 3336 times

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