A1000 to PC Cable - Disk Drive Emulator

[hornpipe2]

I've been kicking around the idea of building a cable to connect my aging A1000 to my PC.  For those familiar with the Atari 8-bit computers, I was hoping to develop a similar project to the SIO2PC cable and software: I'd like to use my PC and large hard drive as a "disk drive emulator" - serving up Amiga floppy disk images over a custom cable behaving just like a real disk drive.  This would be totally transparent to the Amiga, which would see it as if it was any other disk drive connected to DF1.

One of the goals is to be able to boot my Amiga even if I didn't own a working Kickstart or Workbench disk - that way I wouldn't have to worry about disk or drive failure.  Let's get a few questions out of the way first, essentially to determine which drive the cable would replace (internal or external):

1) Can the Amiga boot Kickstart or Workbench from an external drive?  What about just Workbench (doing the soldered-in Kickstart ROM hack is an option if that's the only thing that requires the internal drive)

2) Are the connectors the same for the internal and external drive?  Are there any documents available describing how the Amiga actually communicates with the drives?

3) Would this be of much use to anyone besides A1000 owners?  Are there any other projects like this?  I'm aware of things like Amiga Explorer which communicate over a null-modem cable, but those aren't transparent to the Amiga, nor could they be used to boot the Amiga.

[marauderII]

I could use something like that. Got 2 a1000's collecting dusk
because of bad drives/ks disk. I power them on sometimes just to hear the boot sound.

[InTheSand]

Hi,

This sort of thing could definitely be useful!

In reply to your questions:

1. An A1000 will only boot Kickstart from the internal drive, and as far as I know, the 1.x Kickstarts will only boot Workbench (or anything else) from the internal drive. 3.x (and possibly 2.x) will check all floppy drives for bootable disks

2. The connectors are different (34-pin IDC internal ribbon vs 23-pin D-type external). External drives have additional logic whereas internal drives just plug straight in

3. Yes, this would be of use to other Amiga owners! See tnt23's floppy emulator for a project with a similar aim

 - Ali

EDIT: And... welcome to A.Org!

[weirdami]

@marauderII

Did you try a dirive cleaner disk? I had a "bad" drive an an A1000 once and I cleaned it out and it worked after that. I also used a can of air.

[marauderII]

Yea, I've cleaned them a few times before. But all my original disk are corrupt now (thanks to Disk Doctor). I use cloanto amiga explorer to transfer adfs to my A1200 then write to 3.5
floppy then power up the A1000 (My first A1000 bought from soft hut in 1986 for $1695)(thanks dad). I just like the A1000  
desktop case and all the hours i spent typing ed s/startup-sequence ect in cli. It would be so nice to have an old pc hide under the desk with all my disks. Just like i have with my c64/128.
 


   

[Noster]

Hi,

> 1. An A1000 will only boot Kickstart from the internal drive, and as far as I know, the 1.x Kickstarts will only boot Workbench (or anything else) from the internal drive. 3.x (and possibly 2.x) will check all floppy drives for bootable disks
The advantage of the A1000 is it could use different Kickstarts and special ones like the "United Forces Antivirus" short UFO 1.3 or the "Level 42" Kickstart 1.2. Both these Kickstarts are able to boot the Workbench or a game from an external drive.

I think the "ROM Kernel Reference Manual -- Hardware" is a good place to find something about the communication of the Amiga with the disk drives.

Generally I would say that it is much easier to take a LapLink-cable and an older PC (Pentium I with Wind#*?& 95) and use the PC as an external non-autobooting harddrive using the "PC2Am" software that could be found at Aminet: http://de5.aminet.net/comm/misc/PC2Am308.lha
Works quite good with my A500+ and an old 486DX2/66 PC.

Noster