Re: "To manually boot a disk..."

[ntohsepuasmch@centurytel.net (Theusch Family)]

On Sat, 07 Oct 2000 06:46:38 GMT, Scott Sidley <sidleyr@jb.saic.com>
wrote:

>
>
>Theusch Family wrote:
>
>> Hiya kids.
>>
>> I am attempting to make a sort of "network drive" for an Apple IIe.
>> It involves using a serial null-modem connection to simulate the
>> actions of what the RWTS IOB does with disks, except it retrievs disk
>> info from a pc running "server" software.  I was hoping to be able to
>> "boot" a "file server" "disk", therefore completely eliminating the
>> need for a disk drive, except for my network booter program.
>>
>> <snipped>
>>
>> What exactly would I have to read and execute from a DOS 3.3 disk
>> (ProDos disk, any disk?) to start up the "Bootstrap Loader"?
>> Eventually I would have to modify everything to be redirected through
>> the null-modem ( !! ) but that is a different task.  If somebody could
>> just explain the booting process in hazy detail, I will be satisfied
>> for awhile.
>>
>> Would I just sorta read in Track 0, sector 0, to address $800, and JMP
>> to that?
>>
>> Thanx.
>>
>> larva_jt1@yahoo.com
>
>If you are going top emulate a DISK, all you need is the abilty to move
>blocks.  A Block is
>512 bytes.  You could put a small driver in the serial card rom that makes
>it look like a prodos
>(or pascal 1.1) block device.  The initial boot loader requests from the
>server the boot block,[
>the boot block on a dos 3.3 or prodos disk is track 0 sector 0 (prodos's
>boot block then loads in track 0 sector 2 the second half of the prodos
>boot block)] and copies it to $800 then jumps
>to $801.  You can keep the boot blocks seperate on the server allowing
>both dos 3.3 and prodos boots from your server.
>
>It would not be all that fast with a 6551 ACIA, but certainly doable.
>
>Once you work out the transfer protocol you are mostly there.
>
>
Thanx.  I will work out a test for your theory in a day or two, and
let you know how it goes.