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Path: news.uiowa.edu!news.physics.uiowa.edu!math.ohio-state.edu!howland.erols.net!newspump.sol.net!news.mindspring.com!L2Co From: L2Co@mindspring.com (Larry Knight) Newsgroups: comp.sys.apple2.programmer Subject: Re: Apple II Email (Network Connections) Date: Thu, 10 Oct 1996 21:19:08 -0400 Organization: The L2 Company Lines: 82 Message-ID: <199610102119086450077@user-168-121-33-105.dialup.mindspring.com> References: <32546DD2.7CF3@wctc.net> <3255CE3F.4C16@uwrf.edu> <3255D023.4090@wctc.net> <53e6i8$493@cisu2.jsc.nasa.gov> <325B944D.2414@wctc.net> NNTP-Posting-Host: user-168-121-33-105.dialup.mindspring.com X-Server-Date: 11 Oct 1996 01:18:32 GMT X-Newsreader: MacSOUP 2.2b3 OK, I am new to this discussion, and completely ignorant of Apple II hardware, but I think I can be of some service. I am a hardware engineer that designs cache cards for Power Macs, and in a former life spent a little time with LocalTalk issues when I worked for Hayes (the modem guys). A few comments/questions: 1: At the physical layer, LocalTalk (or PhoneNet) boxes are little more than transformers (open one up sometime and look). They allow the RS-422 (NOT RS-232!) outputs of the Mac serial ports to drive the signal onto the "bus" which is the two-wire LocalTalk or PhoneNet cabling that is shared by multiple devices. RS-422 is a "push-pull" differential output and input system which has superior noise cancellation properties than "single-ended" drive types like RS-232. Don't worry though, the conversion between RS232 and RS422 is very simple and cheap. 2: LocalTalk runs at 230,400 bps, and not at any slower speeds. Not only that, but it is driven by a particular modulation scheme called Manchester II encoding, and moreover it uses a SYNCHRONOUS protocol (I think it is SDLC, but don't quote me on that). Basically, to do LocalTalk easily, you pretty much should use the chip that Apple uses on their motherboards - The SCC (Serial Communications Controller), or 8530, available commercially from either Zilog (are they still around??) or AMD (definitely still around!). 3: Does the Super Serial Card have the SCC on it, or just a simple UART? If anyone has one handy that they can look at, just read the numbers on the largest chips on the board, and I can probably tell you what kind of communications chip that they have there. If it is NOT an SCC (just look for "8530" somewhere on the chip markings), you will have big obstables to overcome in implementing AppleTalk. If the Super Serial Card DOES have an SCC on it, then you're far along the path. The only remaining obstable is the proper programming of the part, etc. (I'm not saying that is trivial, but at least the hardware support is there). 4: If the Super Serial Card does NOT have an SCC on it, the most straightforward path seems to get Apple to allow someone to make the Apple II workstation board again, license-free (which I will guarantee without even looking at it that it has an SCC on it). I own a small hardware company (we engineer and manufacture cache cards for Power Macs), and would possibly be interested in manufacturing this board again, but certainly would need Apple's blessing. Can anyone loan me a Apple II workstation board for a few days so I can take a look at one to see what the manufacturing costs would be? It can be dead or alive. If you have a dead one, could I keep it? Comments? Does anyone have a clue as to whom should be contacted within Apple about this? Anyone out there know WOZ? He may be supportive of this movement to give the venerable Apple IIs another shot of life. There are lots of schools with these things just lying around gathering dust, and they could make great email stations for students! By the way, in this discussion, I have not heard OfficeMail mentioned. It is from Claris, and is an Email POP server for a LAN. Any POP client can talk to it over LocalTalk OR TCP/IP - either will work. Of course, Claris would like you to use Emailer, which is a client for OfficeMail, and is also a great Eudora competitor as a general internet and online service email reader. OfficeMail would make a nice server for the Apple II clients. Moreover, since it is from Claris, which is owned by Apple, there could be the remote possibility of some help from them in this adventure! It is also CHEAP - $275 or so for the server sofware, and there are NO license fees for adding clients (if you use a freeware mail program like Eudora). Gee, I wonder if Claris would make a freeware Apple II version of Emailer that is HIGHLY stripped down? Wouldn't THAT be a kick! And a hell of a public service to the many schools owning these machines. TCP/IP would not be necessary, since the Apple II would be using LocalTalk. Hey, WOZ, wherever you are! Can you chat up some of your friends at Claris? Can you give us some guidance here? Larry Knight -- The L2 Company http://www.mindspring.com/~l2co 3544 Jefferson Township Pkwy eMail: L2Co@mindspring.com Marietta, GA, USA, 30066-1782 International: +1 770 641 9650 FAX : +1 770 641-9433