From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Schmitz Subject: Re: Atari ROM port ISA Date: Sun, 22 Apr 2012 03:44:10 +1200 Message-ID: <4F92D5CA.1000205@gmail.com> References: <4F8BCF49.4060109@gmail.com> <20120417050500.GA14387@cynthia.pants.nu> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail-pb0-f46.google.com ([209.85.160.46]:39446 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751938Ab2DUHtJ (ORCPT ); Sat, 21 Apr 2012 03:49:09 -0400 Received: by pbcun15 with SMTP id un15so1897619pbc.19 for ; Sat, 21 Apr 2012 00:49:09 -0700 (PDT) In-Reply-To: Sender: linux-m68k-owner@vger.kernel.org List-Id: linux-m68k@vger.kernel.org To: Thorsten Glaser Cc: Michael Schmitz , linux-m68k@vger.kernel.org Hi Thorsten, >> Thanks for explaining this to me - to be honest I've never cared too >> much about ISA and friends. > No problem. (I practically grew up with them, so while the knowledge > isn=E2=80=99t fresh, some is there.) I grew up without computers - the first I used was a TR440 mainframe :-= ) >> I'll check the layout - my guess would be that there's no memory >> read/write selects wired up on the adapter. The RTL8019 doesn't need >> them, the ISP1160 on the NetUSBee doesn't need them either. > I=E2=80=99d guess the same. You=E2=80=99d need them for things like a= n ISA graphics > card, but not (most) I/O devices. Only /IOW and /IOR are wired up. Only A0 through A4 are wired up (from=20 A9-A13). >> If someone ever comes up with a way to hook up a fully featured ISA >> slot to the ROM port (mapping ports 0x00 to 0x7f to IO and above to >> mem access should be possible) we might revisit the code. For now, >> anything except for 8 bit IO can be turned into dummy functions or >> compile warnings. > Might be nice, if possible. But for now, that would indeed be > the way to go (and clean up code). I've had a look at the NetUSBee docs and see that the USB part of it=20 does require 8 bit writes but little endian 16 bit reads. So we will=20 need to retain the 16 bit reads for potential USB support there. Cheers, Michael