The MacTerminal MINI-HOWTO
Robert Kieslingv1.4, 9 November 1997
This mini HOWTO describes the 1,002nd use for a dead Macintosh (grin): how to configure the Mac for use as a Linux terminal. Configurations using getty and the terminal program kermit are described, as well as using kermit peer-to-peer networking between between Linux and a Macintosh. This document may be reproduced freely, in whole or in part, provided that any usage conforms to the general copyright notice of the HOWTO series of the Linux Documentation Project. See the file COPYRIGHT for details. Send all complaints, suggestions, errata, and any miscellany to email@example.com, so I can keep this document as complete and up to date as possible.
This mini-HOWTO should give you some Insanely Great ideas for how to make your Macintosh work with Linux. Unfortunately, I have been very busy, and so I haven't been able to include even half of what I wanted to include, like using MacTCP and Open Transport to connect to your Linux box via a PPP line. That will need to wait for future versions.
This mini-HOWTO doesn't cover networking with LocalTalk and AppleTalk, either. I might explore these avenues if there's enough interest in, say, printing to a LaserWriter printer from Linux. Otherwise, it seems to me that such applications, being more trouble than they're worth (not to mention pricey), are beyond the scope of this document.
I don't plan to cover MkLinux in this document, either. It's more than adequately documented elsewhere.
So if you have ideas for this document, drop me a line at the e-mail above. Both systems embody a lot of the beginner's mindset as well as technical prowess, and in my opinion they don't talk to each other nearly enough.
To set up a serial link between a Mac and a Linux machine, you will need, on the Linux side, either a DB9 Female-to-DB25 Male serial cable or a DB25 Female-to-DB25 Male serial cable, depending on your serial port. On the Macintosh side, you will need a DIN9-to-DB25 Male high-speed modem cable.
Make sure that the cable is labeled a "high speed" cable, because some older Macintosh cables are configured with their handshaking lines tied high, which makes them useless for high-speed serial connections.
You will also need a null modem adapter, available at Comp USA, Radio Shack, and similar outlets, and a DB25 Female-to-DB25 Female serial gender changer to connect the two serial cables.
I have heard that Mac printer cables are really null modem cables in disguise, but I can't confirm this. Some of them are DIN9-to-DIN9 anyway, and wiring one into a serial link would be more trouble than it's worth.
If this sounds like Greek to you, read the Serial-HOWTO for details of RS-232 cable configurations and data transmission protocols.
Before connecting the Mac and the Linux machines, you should determine
that you have a working serial port on both machines, either by
connecting a modem and dialing out to another computer with
The latest version of minicom is available from sunsite.unc.edu/pub/Linux/apps/serialcomm/dialout and mirror sites.
ZTerm is a complete, easy to use comm program. Unfortunately, it's shareware. A current version is available from mac.archive.umich.edu and outlets like it.
You should strongly consider using
If you have another way to determine that the serial ports of the two machines are operational, feel free to use that. The point is to ensure that both machines have working serial ports.
Making the actual serial connection should be easy, given the directions above. In case it isn't, the connection looks like this:
Linux PC DB9- or DB25- Null Gender DIN9-to- MacBox --------- to-DB25 male Modem Changer DB25 Mac -------- | | serial cable. | | | | Serial Cable | | | |-----------------| |--| |-----------------| | | | | | | | | | --------- Adapter --------
This is the most transient of all the configurations described here. It requires the least amount of system configuration, although in operation, it is the more difficult to use of the systems described here.
In brief, you start
You should ensure that
With that in mind, your
echo Executing site initialization file /usr/local/bin/ckermit.local.ini.... set prompt Chanel3 > set line /dev/ttyS0 set baud 38400 set send packet-length 2000 set receive packet-length 2000 set block 3 set file type binaryThen, in your
take /usr/local/bin/ckermit.local.iniOn the Macintosh side, set the same communication parameters for bps, stop bits, parity, and word length. Some older versions of Mac Kermit do not support 2k packets, so you might need to set a smaller packet size. Howerver,
To actually communicate over the link, you need to enter server mode
on either the Mac or Linux side. It doesn't matter which. See the
This is one of the very few
When transferring binary files between the two systems, you should use
If you have a text file which inadvertently ends up as a data-only
file on the Mac, it's likely that it won't even appear in an Open
dialog list box. What you need to do is open the file with ResEdit,
which is available from
There are many other neato things which TeachText can do, so it's worthwhile to keep it permanently on your Mac. The book Voodoo Mac, by Kay Yarborough Nelson, is a good source of tried-and-true Macintosh tricks that use ResEdit, TeachText, the Finder, and other overlooked programs.
Configuring Linux to use the Mac as a
Essentially, what you want to do is start
On the Linux side, the serial line must be configured with a
T1:23:respawn:/sbin/getty -L ttyS0 9600 vt100Be sure to substitute the appropriate serial device for
This command tells
Also, if you use something besides vanilla
The Serial HOWTO provides helpful details on how to configure
To transfer files back and forth between the Macintosh and the Linux
machine, you can (via the Mac's Kermit) issue the
set prompt Linux-kermit >Otherwise, remembering which machine you're on can quickly become confusing.
This method should work equally well for any other Mac terminal
program. If you have ZTerm, you can use
If you have questions about any of this material, or suggestions for
future directions of Mac-Linux serial-line connectivity, don't
hesitate to drop me a line at