Marcel Kilgus wrote:
> Tony Firshman wrote:
>   
>> I will get one of these and play:
>> http://www.ghielectronics.com/details.php?id=5&sid=6
>>     
>
> I've read the manual. Actually this is a pretty neat device and easy
> to program. The problem is the serial link. While it could be easily
> used to attach USB keyboards and mice to the QL, it's probably too
> slow for anything else (flash memory access, printing). I mean, we're
> talking the speed of a Microdrive here, even floppy discs are
> blazingly fast in comparison.
>   
Do I notice a comment on microdrives as /slow/? What is it... 7 seconds 
to transfer 100K - which equals somewhat better than 100 bits/sec.

A floppy, once you allow for interleave, comes nowhere near that? I.e. 
when transferring the /whole/ of a microdrive, versus the /whole/ of a 
floppy. the floppy may just outperform the md. However, while 
transferring a single file, the md files are /usually/ contiguous (and 
for program load, this doesn't even matter), so the transfer rate is 
still high. but the floppy sectors will come up with every 3rd or worse 
and the performance will dive.

Speeds come in many flavours. The access time, instantaneous date rate 
and sustained data rate, for example. For md, the access time is indeed 
crap (average 3.5 seconds!), but both the others are the same, and quite 
good. For a floppy drive, access time is not brilliant (300ms?), but the 
sustained rate is worse than 1/3rd of the instantaneous rate (to some 
extent dependent on formatting - and I'm assuming the standard 
interleave and skew, which are there for a good, if historic, reason :-> 
). Horses for courses, as ever.

-- 
Lau
http://www.bergbland.info callto://LauReeves (see http:www.skype.com)
Get a domain from http://oneandone.co.uk/xml/init?k_id=5165217 and I'll get the 
commission!

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