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Old 05 October 2017, 12:57   #1

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Trackloader without working /RDY pin

IIRC, the last generation of Amiga Technology A1200 got floppy disk drives without a working /RDY signal? Now I'm trying to make my trackloader compatible with those.

Currently I'm using the /RDY signal in these situations:
1. After turning on the motor, /RDY becoming low shows me that it reached nominal speed.
2. Before setting ADKCON, DSKSYN and DSKLEN to start the DMA transfer, I check /RDY to make sure the drive is ready.
3. At the beginning I'm reading the drive's serial ID code via /RDY to determine which drives and what kind of drives are connected.

For 1. the solution is simple: I will use a timeout of 500ms. When /RDY still didn't become low I will just assume the motor is running at nominal speed and continue.

I'm not sure anymore why I need to check /RDY at 2. Before starting a DMA transfer I usually step the head or change the side, which is followed by a settle-delay of 25ms anyway. Maybe I can remove that?

For the last case (3.) I have no real solution. I guess that a non-working /RDY will always stay high, so I will probably read a $ffff ID, which correctly identifies a 3.5" DD drive. This may also be the reason that trackdisk.device still works with these drives.
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Old 05 October 2017, 13:47   #2
Omnia fert aetas

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Hi phx, from my loader:
1) no check of /RDY at all (500ms delay), various check after DMA started (DSKSYN bit, timing, ...)
2) settle time respected after delay (18ms)
3) i don't care about ID check.. but is this significative? isn't the floppy hole that make difference?

Last edited by ross; 14 November 2017 at 23:45.
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Old 05 October 2017, 14:03   #3
move.l #$c0ff33,throat

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For 1 I'm also using a 500 ms delay, if the RDY signal is not received during that time I'm trying to read a track which will fail if drive is not ready. This solution works fine for me.

For 2 I also don't see why you need to check the RDY signal again.

For 3 maybe using trackdisk.device (during boot) could help with drive ID's?

Last edited by StingRay; 05 October 2017 at 14:53. Reason: typo
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Old 05 October 2017, 16:52   #4
ex. demoscener "Bigmama"
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The drive ID's are available at boot time from trackdisk.device.. I attached some code (which is a bit shady, but should get you in the right direction) to this post a while back.
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Old 05 October 2017, 17:39   #5

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That's all I need to know. Thanks to all!
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