[Coco] Q: Burke & Burke hard disk controller

[Phill Harvey-Smith]

Ciaran Anscomb wrote:
> Steven Hirsch wrote:
>> Or, will a 16-bit IDE drive work while throwing away half its 
>> capacity (no access to the upper byte of data)?
> 
> Yes, this definitely works.  I recently picked up an IDE/CompactFlash
> interface off Ebay for the BBC Master, and it is an 8-bit interface.
> 8 bits of each 16-bit transfer are simply discarded.

That wouldn't happen to be the RetroClinic one would it ? If so what do 
you think of it ?

> Looking around a bit revealed that at least the most common ATA commands
> are all contained within 8 bits.

Something I started playing with, and must get back to is a 16bit IDE 
interface for XT type computers, my idea was to buffer the high byte on
reads, and the low byte on writes so as to take advantage of 16 bit 
read/write operations having less fetch/execute overhead. It did make a 
difference acording to nortons speeddisk.

I guess the same principle could also be applied to the CoCo/Dragon, but 
would probably have little advantage on the BBC, which is 6502 based, 
from my little knolwege(sp?) of 6502, it has no 16 bit operations.

Cheers.

Phill.

-- 
Phill Harvey-Smith, Programmer, Hardware hacker, and general eccentric !

"You can twist perceptions, but reality won't budge" -- Rush.