Newsgroups: comp.robotics
Path: brunix!sgiblab!munnari.oz.au!mel.dit.csiro.au!its.csiro.au!dmssyd.syd.dms.CSIRO.AU!metro!extro.ucc.su.OZ.AU!gregs
From: gregs@extro.ucc.su.OZ.AU (Greg Schiemer)
Subject: question on anticipated problems with 68HC711P2
Message-ID: <gregs.755351752@extro.ucc.su.OZ.AU>
Summary: SCI with MI capability, programmable chip selects, 31.25 Kbaud
Keywords: SCI
Sender: news@ucc.su.OZ.AU
Nntp-Posting-Host: extro.ucc.su.oz.au
Organization: Information Services, Sydney University, Sydney, NSW, Australia
Date: Wed, 8 Dec 1993 11:55:52 GMT
Lines: 36


        68HC711P2FN

        Does anyone know whether there are two two enhanced SCI Ports on the 
        68HC11P2 (as indicated in the Hc11 Taxonomy kindly posted by Alan
        Kilian) or three (as it says in the 1991 Advance information) ?
        In the advance information two are labelled as having "with MI
        Capability". Surely this does not mean a MIDI interface. Can anyone 
        tell me if it actually does ? (I sure hope its yes! On both the A1
        and the 811E2, using an 8 MHz crystal, and prescaler bits SCP1=1
        and SCP0=0, one can produce the 31.25 kbaud necessary for MIDI).

        Another question relates to programming the programmable chip selects 
        when one doesn't have access to a development system. The problem is 
        that unless one starts with a program in external ROM, one does not 
        have a way to initialise the chip selects. Does one have to first 
        build an external address decoder to enable the P2's internal chip 
        selects or is there some other way ? (I've squeezed my way into an A1
        and 811E2 before without the help of an evaluation module, but there
        is much more guess work involved here).

        Is the P2 shipped set up with a wacky SCI baud rate like the 811E2
	was ?

        These are some of the problems I anticipate. If anyone has already
        encountered some I'd appreciate hearing from you.

	Cheers


	Greg Schiemer
	Lecturer in Composition & Electronic Music
	Sydney Conservatorium of Music


	gregs@extro.ucc.su.oz.au
