Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!think.com!sdd.hp.com!cs.utexas.edu!uunet!mcsun!ukc!inmos!brac!davidb
From: davidb@brac.inmos.co.uk (David Boreham)
Newsgroups: comp.sys.transputer
Subject: Re: host/transputer link speeds?
Message-ID: <16425@ganymede.inmos.co.uk>
Date: 5 Jun 91 09:34:17 GMT
References: <1991Jun4.133704.21008@cmcl2.nyu.edu>
Sender: news@inmos.co.uk
Reply-To: davidb@inmos.co.uk (David Boreham)
Organization: none
Lines: 34

In article <1991Jun4.133704.21008@cmcl2.nyu.edu> dimitrov@lab.ultra.nyu.edu (Isaac Dimitrovsky) writes:
>
>[]
>Does anyone know what the fastest link you can get between a PC host
>and a transputer on a board is? I was under the impression that it
>was 300Kbytes/sec, which is too slow for us. If we could get up around
>two Mbytes/sec, transputers would look very interesting for our
>application (it involves real time video compression).
>


``Bog-standard'' PC interface cards (like the INMOS B008) do max out
at 300K for the _HARDWARE_. Generally you would need to write your
own (or modify something else) software to achieve this speed in
an application however.

Links themselves have a 1.7Mbyte max data rate and so your 2Mbyte
target would require two simultaneous links. To achieve this look
for boards which use a transputer rather than a link adaptor as
the interface device. I've seen one from Transtech which does 
1Mbyte on one link through a device driver. Can't remember if it
supports multiple links. There are a few other cards out there
doing similar tricks but I forget who makes them.

As another thought, would it be possible to avoid sending 
the data to the PC altogether ? Perhaps by using a JPEG TRAM 
or transuter-based display board ?

David.


David Boreham, INMOS Limited | mail(uk): davidb@inmos.co.uk or ukc!inmos!davidb
Bristol,  England            |     (us): uunet!inmos.com!davidb
+44 454 616616 ex 547        | Internet: davidb@inmos.com