Date   : Fri, 23 Nov 1990 17:40:00 GMT
From   : swrinde!cs.utexas.edu!hellgate.utah.edu!fcom.cc.utah.edu!cc.utah.edu!cc.usu.edu!slsw2@ucsd.edu
Subject: Amstrad CPC -- HDs

In article <1990Nov20.212904.14578@actrix.co.nz>, ewen@actrix.co.nz (Ewen
McNeill) writes:
> In article <1990Nov19.090518.3479@simasd.uucp> donm@pnet07.cts.com (Don
Maslin) writes:
>> 
>> Assuming that it is a Z-80 based machine (display of ignorance here!), it
>> seems that it might be possible to get a HD kit from Emerald Microware which
>> uses a small daughter board that plugs into the Z-80 socket plus the
WD1002-05
>> hard disk controller... 
>  
> The machine is definately Z80 based, so your solution might well
> work.  Software modifications of the BIOS could be difficult, as
> could be keeping up with the speed of a HD.  The machine runs at
> 4Mhz with one wait state (effective speed is said to be 3.3Mhz).
> The machine does not support DMA, or Interupt driven Disk IO (the
> floppy IO is done by polling the controller as is the serial IO --
> both _cannot_ be done at the same time :-) 

Actually, the WD1002-05 has a sector buffer on board. The data is transferred
from the disk into this sector buffer, after which the host processor can
pull the data from the sector buffer at its leisure. DMA is not required, nor
are interrupts.
-- 
==============================================================================
Roger Ivie

35 S 300 W
Logan, Ut.  84321
(801) 752-8633
==============================================================================