Newsgroups: comp.sys.transputer
From: davidb@ndl.co.uk (David Boreham)
Subject: Re: T222 serial interface problem ???
Organization: Network Designers Limited
Date: Sun, 18 Sep 1994 21:15:41 GMT
Message-ID: <CwCGE6.F19@ndl.co.uk>

In article <1994Sep14.073630.17426@lugb.latrobe.edu.au> cleeve@lucifer.latrobe.edu.au (Jason Cleeve) writes:
>Does anybody have experience using 16 bit Transputers and 
>serial interfaces ?
>I'm trying to connect up a serial port to a T222 transputer 
>using a Rockwell 6551.
>The problem I've got is when I try to read an 8 bit register 
>on the 6551 I actually get 2 reads which causes problems.
>I've tried to use Load Byte (LB), but this also seems to 
>produce 2 read strobes.
>It also happens when I try to write a byte to an 8 byte location
>using Store Byte (SB).

You've used MemBAcc to make the processor access a n "8-bit" device
haven't you ? From my totally aincent transputer datasheet:

"The MemBAcc pin can be set at the start of a memory interface cycle
to cause the memory interface to perform two byte access cycles."

Don't use this feature. Use 16-bit wide mode as normal and mask off
the upper bits.


