new toy!

From: Don Maslin <donm_at_cts.com>
Date: Sun Jan 31 23:15:34 1999

On Sun, 31 Jan 1999, Allison J Parent wrote:

>
> <Actually, on the downstream side of the adapter card you are tremendously
> <close to an IDE interface. As I understand it, the IDE interface is
> <premised on the commands that are required by the WD1002-nnn controller.
> <zI have forgotten the exact model, but it must be near to the WD1002.
>
> Incorrect.

I erred in not defining my thought more completely. What I had in mind
when I mentioned IDE was the 8-bit IDE that was used early on in XT class
machines with drives like the ST-351A/X and others.
 
> IDE is the buslevel equivelent of the ISA16 card WD1003WA. The register
> format, addresses of the registers are identical, the interface is also the
> same save for there are only three addres bits and two selects(like chip
> select) where the board would take a full 10 bit address and decode it.
>
> The 1002 HOST interface has a different address, register command
structure > though there are similarities wbeing both from WD.

How do the above relate to the 8-bit IDE interface?
 
> To do a IDE on kaypro you would need to do the 8<->16 bit translation
> and from what I have here there is not enough addresses brought out to the
> host adaptor plug. That means a CPU piggyback adaptor (GIDE is one case).
> SCSI would be easier as a cpu interface but the SCSI bios is a nightmare
> for the 5380 type chips.
>
> In any case adding a hard disk to kaypro requires utility software, an
> interface and BIOS.

But if you have the TurboROM, you already have all of that with the
exception of the interface. How big a chore would it be to adapt the
WD1002/Host interface to the 8-bit IDE? If one could do that with
minimum difficulty, it could provide an easy 40mb of HD storage - a huge
amount on a CP/M machine.
 
> Going the turborom route and putting two to three 3.5" disks is easier.
> With 3.5" drives there is auto write portect on power down so you dont need
> to eject the disks and with the that would be 2.3mb of available storage
> plus the 360kb drive for compatability. I have one setup in such a mannor
> with an old IBM PS/2 drive inside the case (I treat it as 781k hard drive)
> and two drives on the front (3.5" and 5.25" 360k). For what I use the
> kaypro for that's plenty of on line storage.
 
> To do 1.44mb would require far more effort due to data rate and the fact
> that DMA is not available so it would be hardware mods for floppy controller
> and also big time bios mods.

Agreed!
                                                 - don
 
> Allison
>
Received on Sun Jan 31 1999 - 23:15:34 GMT