Re: AppleTalk to Ethernet bridge software for Mac?

[dempson@actrix.gen.nz (David Empson)]

Mark Cummings <figjams@primus.com.au> wrote:

> I found out that installing the Apple LocalTalk Bridge software was trying
> to use the printer port but that AppleTalk was still on the modem port. That
> must be the default and I couldn't see how to change it anywhere.

You are confusing two independent settings.  The AppleTalk control panel
and LocalTalk Bridge are completely separate.

The setting in the AppleTalk control panel determines which port the Mac
itself is using to connect to the AppleTalk network.  Assuming you want
to use Ethernet, then it must be set to Ethernet.

LocalTalk Bridge hooks into the AppleTalk support in order to capture
all received AppleTalk traffic (and AppleTalk packets generated by the
host machine), forwarding appropriate packets out the printer port; it
also receives packets from the printer port and forwards them to the
AppleTalk network (and/or local machine) if appropriate.  LocalTalk
Bridge actually contains its own implementation of the low-level parts
of the AppleTalk protocol stack, which is limited to supporting the
serial port.

> This is why I lost my printer from the printer port and AppleTalk stopped
> working on the modem port. Anyway I disabled it and reconfigured AppleTalk
> to use the printer port, and the printer on the modem port, swapped the
> cables over and now both are working. I assume LocalTalk Bridge is OK now,

It won't be.  You must set the AppleTalk control panel to use Ethernet.
If you have it set to the Printer Port, then LocalTalk Bridge must have
been disabled - it probably didn't start up due to the printer port
being used by other software, in this case the AppleTalk protocol stack.
If you open the LocalTalk Bridge control panel, it will probably say
that it "will be enabled at startup" (or words to that effect), but
isn't enabled at present.

You should be able to get everything working correctly by setting
AppleTalk to use Ethernet, then restarting.  This will allow LocalTalk
Bridge to use the printer port.  The Mac should be able to continue
accessing LocalTalk devices like the ImageWriter II.

> Just to put you in the picture this is my setup, not as good as Bart's but
> I'm new at networking :)
> ASCII art begin...
> abbreviations:
> === 10Base2
> --- AppleTalk
> ~~~ Parallel
> ... Serial
> (P) printer port
> (M) modem port
> (S) serial port
> (E) ethernet port
> (AT) AppleTalk
> 
>       PC2        PC1           Quadra        ClassicII  IIGS       IWII(AT)
> etc===(E)========(E)===========(E)(P)--------(M)--------(M)--------(P)---etc
>                  (P)~~~Epson...(M)                      (P)...14.4 Modem
>     33.6 Modem...(S)

[snip] 

> What I would like to do...
> 
> 1. Use the Epson printer from the ClassicII or IIGS on the AppleTalk side.
> The Epson is not AppleTalk compatable, I can't use it via the modem port on
> the Quadra, so can I use it via the LocalTalk Bridge and the PC1's printer
> port (sneaky hey ?)
> The Epson is a Postscript printer, but I don't think it supports the
> AppleTalk PAP protocol you mentioned. Is this what the AppleTalked IWII
> uses. If so the the Epson can't do it.

What model and type of Epson printer is this (inkjet or laser, model
number)?

If the Epson doesn't have hardware support for AppleTalk (either
LocalTalk or Ethernet), then it won't support PAP, which is the
AppleTalk Printer Access Protocol.

You might be able to use it with a device like the HP JetDirect (network
print server), which provides an Ethernet connection to a printer via
its parallel port.  The JetDirect implements the various network
protocols, so the printer doesn't need to.  This would allow the Epson
to be accessed from any networked PC, but access from a networked Mac
(using AppleTalk protocols) requires that the printer have a
bidirectional parallel port.  I'm not sure whether there are any
additional requirements, as I've only used it with a printer which
supports AppleTalk directly.  I know that it does work with several HP
Deskjet models which in themselves don't have AppleTalk support.

Assuming it worked, then you would be able to print to it from both PCs,
all Macs, and as long as its Postscript implementation is old enough (or
sufficiently backward compatible), you might even be able to access it
from the IIgs.  I haven't had a lot of success printing to my HP
LaserJet 6MP (which has a genuine Adobe Postscript implementation) from
my IIgs.

> 2. Connect to the internet from the Classic II or IIGS via PC1's IP sharing
> program.

This part I'm not sure about, because it would depend on the behaviour
of the MacIP support in the Quadra.  You would probably have to run
TCP/IP routing software on this machine, and I don't know how this would
interact with LocalTalk Bridge.  I know that Vicom Softrouter/Internet
Gateway supports MacIP, but don't know whether IPNetRouter does.

This would allow the Classic II to access the Internet, as long as you
are running System 7.5.x (or later) with Open Transport, or have
installed the appropriate classic networking control panels (primarily
MacTCP) under 7.5.x or earlier.

I don't know enough about the available TCP/IP support on the IIgs to be
able to evaluate whether it would be feasible to get it to work in such
a configuration.  The issue is whether it will be able to use the MacIP
protocol running over AppleTalk (as opposed to an Ethernet card or a
direct serial connection using PPP or SLIP).

> 3. Access the PC shared vols from the Quadra, Classic II or IIGS.

Running NT Server or PCMacLan would be one solution for the Macs (as
noted earlier, there may be problems with the user authentication method
supported by the IIgs).

> 4. Access the Quadra or Classic II vols from PC1 or PC2 via the LocalTalk
> Bridge.

PCMacLan should allow one PC to access all Macs running File Sharing.

DAVE would allow all PCs to access one Mac, but I don't know whether it
runs on a 68K Mac.

> 5. Print on the IWII from the PC1 or PC2 via the LoalTalk Bridge on the
> Quadra.

Hm.  (Scratching head.)

PCMacLan, maybe.  I don't know what its printing support is like.

DAVE, maybe (by creating a shared printer for the PCs to access, but it
would probably require leaving the Quadra set to use the ImageWriter
II).

> I don't have the Quadra configured to use the ethernet for AppleTalk, I have
> it set to use the printer port. Otherwise, wouldn't that stop my AppleTalk
> stuff from working on the AppleTalk side ?

No - LocalTalk Bridge implements the AppleTalk protocol via the printer
port.  The AppleTalk control panel must be set to use a different port.