C64 - PC slip connection
- This little document
show how to set-up a SLIP connection between a C64
running Lunix and a PC running Dos or Win9x.
- At the moment I am using
a program called NOS (Network Operating System) to test
Lunix in Tcp/Ip mode
- over a SLIP connection.
- NOS is a program written
for "Ham-radio" community. It was used to
connect remote computers over radio interfaces.
- Over radio channels it
is needed to encapsulate Tcp/Ip in ax.25 frames.
- Anyway, it can handle
pure SLIP connection via rs232 ports, and this is what we
want from it.
- NOS includes several
services, such as TELNET, FTP, HTTP, SMTP servers, and a
- We will set up only
TELNET and FTP servers.
- A serial interface for
C64 userport or equivalent (see related documents for
- A NULL-MODEM cable (see
related documents for more informations)
- Lunix package for C64, "Up and Running", ready for Tcp/Ip.
- NOS 1.10 or later, downloadable at URL:
- Download NOS and copy it in
the directory c:/nos . Do not launch it for now. Create
also a directory called c:\nos\public.
Create 3 new empty files:
- Choose now an hostname for
your system and a IP address. If you do not have a IP
address use 192.168.0.1 . Never use this to browse
Internet, use it only for your c64 network. Let's assume
"johnny" for hostname and 192.168.0.1 for IP
- The ftpusers file contain
information of users and permissions, for our purposes we
need only 3 users, one for c64, one for johnny and one
- The domain.txt file contain
informations about the relationship of IP addresses and
- The file autoexec.nos
contains the informations to setup NOS itself, we will
discuss a bit later on it.
- Edit ftpusers file and add
the following lines:
- anonymous * /public 1
c64 c64 /public 127
johnny johnny /public 1
- The first field is the login
name, second field is the password (* for any password),
the third is the path for FTP access, fourth is the
permission right. 1 means read-only, 127 super-user. (see
Addendum for a full explaination)
- Edit domain.txt file and
add the following lines:
- johnny IN A [192.168.0.1]
c64 IN A [192.168.0.1]
- Fields are separated by
TAB characters. This file defines the relations between
hostnames and IP addresses.
- Edit autoexec.nos file
and add the following lines:
- ip addr [192.168.0.1]
domain trace on
domain translate off
attach asy 0x3f8 4 slip c64 1024 200 2400
trace c64 1111
tcp ti linear
tcp mss 1024
mbox max 8
route add 192.168.0.64 c64
smtp gate 192.168.0.64
- In this file we are
going to define the IP address of the NOS, the trace
(monitoring) of Tcp/Ip frames,
- the asynchronous port
attached to c64, com1 in the example, modify it if
- 0x3f8 4 for base address
03f8 irq 4 (com1)
0x2f8 3 for base address 02f8 irq 3 (com2)
- We also define the
hostname (johnny), the translation of names/IP addresses,
the timing for retries,
- maximum users of BBS and
the route to c64.
- A SMTP (mail) server is
included in NOS, now it has been configured and started.
At the end of the file we start TELNET and FTP services.
- Connect the Null-Modem cable
between C64 side and PC side.
- If you are using Win9x open a DOS
shell and change directory to c:\nos.
Type the name of the executable file (the name may
change, it depends on the release and the compiler,
followed by the options "-d c:/nos" (note the
unix-like slash), eg:
- jn111dls -d c:/nos
- u110l386 -d c:/nos
- If all goes right you will see the
prompt "Jnos>" without any error message.
- Power-on the C64, insert the Lunix
disk and type:
- LOAD "LOADER",8
- After the loading of the loader
- and wait for the prompt of Lunix.
Load the shell:
- L sh
- and wait for "#" prompt.
- Load now all the modules required
for Tcp/Ip. Follow the list:
connd 200 sh&
- With the first line we load the
standard rs232 driver, if you use a swiftlink cartridge
use the right driver,
- then we initialize the protocol
slip with baudrate 2400.
- Baudrate can change due to the
After this we start the Tcp/Ip service with the IP
- Note: this address is fixed, it can
be changed recompiling the kernel.
The last line starts the connection daemon, all the
requests to port 192.168.0.64:200 will cause the
- execution of the shell (sh).
You can start more daemon: for example you can connect
port 100 to process "tcpipstat".
The request of connection to the port 192.168.0.64:100
will open a connection, will execute
- and will close the connection.
- Now you are ready to start connections.
The services provided by NOS are:
- TELNET server:
- From C64 side type "telnet
192.168.0.1 23" In few seconds you should have the
prompt "login:" coming from NOS.
Type "c64", you should now have the prompt
"password:"... type again "c64" and
you will be connected to the
- BBS service included in NOS.
- Note: the port 23 above is the default
port for telnet connection.
Refer to the NOS manual for more infos on the commands of
- FTP server:
- From C64 side type "ftp
192.168.0.1". You will get the same
"login:" and "password:" prompts.
- After this you will use the services
offered by NOS ftp server.
The downloadable files should be in the c:\nos\public
Refer to the Lunix manual for supported commands.
- TELNET Client:
- You can open a telnet connection typing
from the Jnos> command mode the command:
- telnet c64 200
- Doing this the internal resolver of NOS
will translate "c64" into
"192.168.0.64" and will try the connection
- to the remote port 200.
After this the floppy drive will run for few seconds and
you will get the prompt "Lunix ...... #" prompt
- the screen of the PC.
Now you are the second user of the C64 and you can do the
same operations of being directly on the C= console.
- It is possible to open multiple
connections from/to PC and C64, in a real multitasking
It is also possible to have loop connections to test the
performances of the protocol.
Try for example to telnet from PC to C64 and (on the
Lunix prompt) telnet BACK to the PC !
On the screen of Jnos you will read the prompt of your
local BBS, connected passing THROUGH the C64!
- By using the BBS command
"s" (send) you can leave a text message for the
- First log in your local BBS
typing BBS at Jnos prompt, use the "johnny"
- Type in "s c64", then
input the subject and the body of the message; end
message with "/EX" at the beginning of
- a new line. Some Jnos versions
ask for another confirmation.
- Now the message is stored on to
the NOS database, if an user log in with "c64"
account, a message "You have got new mail" will
- Use the commands (R)ead, (L)ist
or (K)ill to handle messages.
Of course you can do the opposite procedure and leave a
message for "johnny", or leave a message for
- who access the BBS.
- Many different releases are
availables on internet, some works fine, some not.
- Not all the releases provide
SLIP protocol over rs232. I've tested the following
u110l386 (version compiled by IW2DVL)
jn111dls (pre-compiled version downloaded from GB7IPH
- As I wrote before, the file ftpusers
defines the permissions of users.
- The last number of the line is
calculated in this way:
- 1 = read files
2 = write files
3 = overwrite existing files
4 = gateway to ax.25 port allowed (useless for the
purposes of this documents)
16 = Telnet allowed from BBS
32 = gateway to NET/ROM nodes allowed (useless for the
purposes of this documents)
64 = Remote Sysop.
- Sum the numbers above to obtain
- Example: An anonymous user should be
able only to read files, and nothing more, so its number
will be "1".
- Example 2: A remote sysop should
have full rights, its number will be 127
- The "64" allow user to
digit the special character "@" at the prompt
of BBS and access to
- Jnos prompt from remote consoles.
- My opinion is that NOS for DOS
is one of more flexible and poweful programs for
- Tcp/Ip experimentations,
unfortunately (at least in Italy) it has been replaced
from Flexnet/Win9x software.
- This package is much more easy
to use and configure.
- Fortunately the development of
NOS is continuing in Linux environment, the Linux
versions are called TNOS.
- Anyway it is a good platform to
test our good old C64...!
- Refer to "official"
NOS manual for the meaning of all the parameters /
- Please send back to me any
question / comment / hint / correction about NOS and C64,
October 25, 1999
Claudio Parmigiani, IW2FER