Path: utzoo!attcan!uunet!mcvax!ukc!stl!stc!idec!prlhp1!paszkows
From: paszkows@prlhp1.prl.philips.co.uk (paszkows)
Newsgroups: comp.sys.transputer
Subject: Splitting up channel comms
Message-ID: <675@prlhp1.prl.philips.co.uk>
Date: 1 Nov 88 08:29:44 GMT
Reply-To: paszkows@prlhp1.UUCP ()
Organization: Philips Research Laboratories, Redhill, UK
Lines: 46


I have two 32 bit words, which for example are made up as follows:

lint 1      bits 00-07  byte1
            bits 07-23  int1 
            bits 23-31  int2 lsb

lint 2      bits 00-07  int2 msb
            bits 08-15  byte2
            bits 16-31  int3


I wish to transmit the two 32 bit integers over a link, but receive them in
the format in which they are made up.
In effect I do

CHAN OF ANY chan.out, chan.in

  SEQ
    chan.out ! lint1
    chan.out ! lint2

  
  SEQ
    chan.in  ? byte1
    chan.in  ? int1 
    chan.in  ? int2 
    chan.in  ? byte2
    chan.in  ? int3 


At present I have tried this over a channel ( not a link yet ) and it does not
work. As far as I am aware, when this is transmitted over a link, the two 32
bit words are chopped into eight bytes, with associated start, one, stop bits, 
so the input link is not aware of the format they are transmitted in, so it
ought to be able to receive them as above.

At a guess, because we have a CHAN OF ANY protocol, is not an identity byte, 
describing what format the next data is in, sent?  ( ie: tt.out.int  etc.. )

Can anyone verify that this will, or if not, can explain why not and why the 
comms over the channel, as described above, does not work.



Thanks.