Drive Numbers on Physical Disk Drives

[Brentarian]

Atari compatible disk drives only supported drive numbers 1-4. Were there ever any mods that changed them to 5-8? Would that have been defined in the drive rom code or was that a drive controller thing? Not that it matters now in the age of SIO2whatever, but I am curious.

[+kheller2]

I believe there was a USDoubler ROM to make the drive act 5-8

Edited September 9, 2016 by kheller2

[Brentarian]

I believe there was a USDoubler ROM to make the drive act 5-8

 

Does anyone know where I can obtain this USD rom that supports drives 5-8? I have a 1050 USD drive I'd like to try this on. I'm also curious to see if it works when flashed to a slot on a MegaSpeedy.

 

 

[+kheller2]

I have yet to find that ROM.. but while searching the Internet I came across this program which I'm curious if anyone has or ever did:

 

"Happy Doubler - Allows you to program your Happy 1050 drives to fully emulate ICD's U.S. Doubler, including formatting disks in the U.S. sector skew (which is not normally possible!). Also allows you to re-program your drive numbers up to D8:, without touching the switches in back! This way, up to 8 - Happy 1050s can be used at once! (4 - programmed as Doublers 5-8 and another 4 - as normal). Completely software based, no installation required! Price: $19.95 (+ S&H).

"

[ijor]

Does anyone know where I can obtain this USD rom that supports drives 5-8?

It is trivial to modify the normal USD rom. These are the first 8 bytes on the ROM:

00000000   1D 2D 35 39 33 32 34 31      .-593241

Do you see the sequence starting at the fourth byte (3241 in ascii)? Guess what they are? Modify as willing ...

Edited October 19, 2016 by ijor

[ijor]

Happy Doubler ... Also allows you to re-program your drive numbers up to D8:, without touching the switches in back! ... Price: $19.95 (+ S&H).

 

I don't remember if the Happy software allows you to specify numbers highers than 4. But the firmware certainly does. You can configure any Happy drive with whatever drive number you want, even higher than 8.

 

Just out of curiosity, the software is selling now, or back at the day?

[ijor]

@Brentarian: Did you try the modification I mentioned? If you do, please let us know how it works.

 

I assume you can use an hex editor to patch the ROM by yourself. If you don't, then let me know and I would sent you a ready made modified binary.

[Brentarian]

I made the changes but haven't had a chance to try it yet. I will try to tonight. Thanks for your help!

[Brentarian]

Ok, starting at byte #4, I changed the values from 3241 to 7685. I flashed the modified rom to one of the USD slots on the MegaSpeedy. I went into SDX and the drive was recognized on D5. Success! The drive selector in the back allows for D6, D7, and D8 now. I haven't burned an eprom yet to try on a real USD drive, but will do so in the next few days.

 

Attached is the original USD rom for D1-D4, and the modified for D5-D8.

USD0104.ROM

USD0508.ROM

[+Nezgar]

Wow guys, I just came across this thread and I'm blown away by you smart people! I've been looking for the USD 5-8 ROM for a long time, and didn't realize how simple the hack was, and what those numbers at the beginning of the ROM meant.

 

The other hack I would like to do to a USD ROM is to modify the stepper speed to make it seek faster, comparible to an 810 or 1050 Speedy. I presume this type of hack would require some checksum recalculations...

[+Nezgar]

"Happy Doubler - Allows you to program your Happy 1050 drives to fully emulate ICD's U.S. Doubler, including formatting disks in the U.S. sector skew (which is not normally possible!). Also allows you to re-program your drive numbers up to D8:, without touching the switches in back! This way, up to 8 - Happy 1050s can be used at once! (4 - programmed as Doublers 5-8 and another 4 - as normal). Completely software based, no installation required! Price: $19.95 (+ S&H)."

 

Another currently available option - I've used the HAPPY.COM included with Steve Carden's RealDOS has a function to upload relocated USDoubler code to a Happy 1050 RAM, and at the same time specify any drive number you wish it to become. It will remain a USDoubler until powered off. You can then even format disks with Ultraspeed skew on a Happy 1050.

 

http://realdos.net/realdos.html

 

"In my RealDos support files I have a program that allows many of the happy function to be used with out having to boot the happy software. Also within the "HAPPY.COM" is a program to turn your happy drive into a ICD Doubler and capable of doing ultra-speed sector skew." - http://www.realdos.net/Duplicator%20Cheerup.html