Configuring the Server
Open up a terminal session and grab the SLiRP package from Aptitude. On Ubuntu variants you can use
, on Debian first
apt-get install slirp
I created this script in my documents path to help configure SLiRP properly. This will be run by MacPPP once it's console session is up.
Type this in below...
slirp -S -b 38400 -P "host addr 10.0.2.1" "dns 10.0.2.3" "asyncmap 000a0000" "debugppp debugppp.log" "debug 1" "mru 500" "mtu 500"
The -b option is Baudrate. My SE/30 works well at this rate. Keacher said his Mac Plus maxed out at 18000. -P is so SLiRP operates as a PPP server.
is the gateway address for the Mac to connect to.
of course is the DNS address for the Mac to obtain DNS.
has something to do with something I don't quite understand.
are the ethernet frame sizes. This is what Keacher found worked best for him.
After saving the file (CTRL + O) make the file executable.
chmod 755 ./Documents/slirp.sh
Next we need to let Linux know to use the serial port as a console port. First we need to figure out which dev is our serial. Use this in terminal.
dmesg | grep tty
(Edit January 2020) Follow the steps below for Debian 14.04LTS and other non-Systemd platforms
Mine shows ttyUSB0 as my serial port. Next I need to create an init script to start the serial console on startup.
to do this. We need this to be owned by root.
# ttyUSB0 - getty
# This service maintains a getty on ttyUSB0 from the point the system is
# started until it is shut down again.
start on stopped rc RUNLEVEL=
stop on runlevel [!12345]
exec /sbin/getty -L 38400 ttyUSB0 vt102
Again CTRL + O to save. As you can see the speed on this connection is 38400. Adjust according to your system.
You can now start and stop the serial console using the following command. This will also start automatically on system boot.
End Non-Systemd section.
Systemd systems (Debian Jessie+, Ubuntu 15.04+, specifically Raspbian)
Systemd is a different beast from init based systems. After running
dmesg | grep tty
in Raspbian you'll need to set the terminal port and speed. Raspberry Pi has an internal serial port but you can also use a USB to Serial adapter.
sudo nano /boot/cmdline.txt
and change the console settings to the appropriate serial speed and port (ex:
If necessary enable and start the console in systemctl:
sudo systemctl enable serial-getty@ttyUSB0.service
sudo systemctl start serial-getty@ttyUSB0.service
You may need to reboot after this but your console should be working.
Configuring the Mac
1. Install MacTCP or OpenTransport (See Downloads at the Bottom of the page).
2. Install MacPPP (The Extension should go in the Extensions folder located in the System Folder
and likewise the Control Panel in the Control Panel folder).
the TCP/IP control panel
4. Select MacPPP. Set your IP and DNS address manually. Your IP should be set to a value between 10.0.2.15-10.0.2.254. (SLiRP uses the lower addresses internally for different functions). Your DNS address should be set to 10.0.2.3.
5. Open the MacPPP Config Control Panel
6. Choose the Port where your serial cable is attached to (In my case printer).
7. Click the config button.
8. Name your server and set the speed to 38400. Set flow control to DTR. Leave Phone num and Modem Init blank.
9. Click Connect Script. Configure with the following. One command on each line. As you will see we're essentially logging in to the terminal and launching our
For those of you browsing without JPG support...
10. Click OK to save script and then Select LCP Options...
11. Change Local ASync Char. Control Map Hex value to
12. Change Local and Remote Max. Receive Unit Values (MRU/MTU) to
13. Click OK and the select IPCP Options...
14. Enter Local IP address as your value from your MacTCP or Open Transport TCP/IP settings (in my case 10.0.2.15) and Remote IP address of 10.0.2.1
15. Click Okay and then Done to finish configuring your connection.
16. Click Open. If all is well you should see the status of the connection opening, running the commands from your connection script and finally two happy faces with the message PPP UP. Open up a web browser and away you go! Happy browsing!
Keacher.com: How I introduced a 27-year-old computer to the web
Serial Cable Guide for the CM11 / CM12 / ActiveHome / Macintosh
Configuring your Macintosh to use SLiRP
LowEndMac.com: Macintosh Serial Throughput
Open Transport 1.1.2
Last Updated: January 2, 2020