At 3:54 PM -0500 7/16/03, Larson, Timothy E. wrote:
>Henry:
>>Most (all?) LaserWriter's will speak serial instead of LocalTalk if
>>you connect a serial cable instead of a LocalTalk dongle to them.
>
>How do I know which is which? 
>Don't the cables look the same?

No.

A LocalTalk dongle will be a small box with a pigtail on it with a 
small round DIN connector to plug into the Mac.  It will also have a 
couple of other female connectors on it for the LocalTalk backbone. 
The box implements the CSMA/CD (Carrier Sense Multiple Access with 
Collision Detection) for LocalTalk so you can have zillions of Mac's 
connected to the same backbone.  It runs at 230Kbps instead of 
10Mbps, but it's the same idea as Ethernet.  And it only requires a 
standard serial port on the Mac.  Kind of neat in it's day.

A serial cable will look like a cable.

Since the 4/600 is an Apple Printer (and not an early model SPARC as 
I first thought) there is probably a small round DIN connecter on the 
printer that looks just like the ones on the SE/30.  If you have what 
they used to call an ImageWriter II cable then you're home free. 
Just plug it in and forget anyone ever told you anything about 
LocalTalk.

You can probably find an old Mac serial cable easier than you can 
find DIN-8 connecters.  If not then you should be able to find 
pinouts somewhere on the net.  The standard cable is a crossover that 
swaps Tx/Rx and the handshaking lines.

>  >So if you can't just send serial data from NetBSD, and you don't want to
>>make a cable, you can get an Ethernet to LocalTalk bridge (they work very
>>well; I'm using one), or you can get something like an LC (II, III) or
>>Quadra 605 as they are small and take very little power, and install the
>>free LocalTalk LaserWriter Bridge software from Apple.
>
>That's what I'm trying to avoid. 
>I figured my SE/30 was small and quiet enough, and could serve other 
>purposes as well since it would be on 24/7.
>I'm going to be bummed if I've decked out this SE/30 only to 
>discover it can't meet my primary goal.

This sounds like a good use for an SE/30.  It's a bit slow to do 
compiles on.  I presume you have an Ethernet card in the PDS.  The 
printer plugs into one of the serial ports.  (You could put a modem 
on the other serial port and run pppd, too.  Hmmm, caching DSN 
server?)

Have fun.
-- 
The opinions expressed in this message are mine,
not those of Caltech, JPL, NASA, or the US Government.
Henry.B.Hotz@jpl.nasa.gov, or hbhotz@oxy.edu