IBM PC Model 5155 connected on Internet

Uploaded by TheNightOcean on 02.07.2009

Hi Everybody ! Let me present you the IBM Model 5155, a portable computer released in 1984
We are going to connect this piece of computer History to Internet !
In order to do so, I will use an HP Laptop running OpenBSD 4.4 as a PPP/SLIP Gateway
You're probably wondering : Why not just connect the 5155 directly to Internet without help of other computer?
Reason 1 : Old computers often don't have NIC, so you can't connect them directly to a DSL Modem/Router
Reason 2: Here in France, phone lines are now often based on VOIP, so the use of old PSTN modems is impossible
The HP laptop (PPP gateway) is connected to a DSL Router via a Wireless NIC
The 5155 is connected to the Laptop via a RS232 Null Modem Cable and an 'USB to Serial' Adapter
It's time to start the IBM 5155
The memory test is very slow on early IBM PCs
The IBM 5155 has in fact exactly the same hardware as his big brother, the IBM PC XT 5160
Same motherboard, same CGA, controlers and I/O cards
The main difference between the two models is the built-in 9'' amber CGA screen of the 5155
That's why the 5155 is so heavy ...
It's simply an IBM 5160 with built-in screen and a carrying handle
RAM test is done, the ST11 controler card will now detect the hard-drive (a RLL Seagate ST238R)
The IBM 5155 is now booting MSDOS 6.22
As you can notice, this is a french version of MSDOS
Let's run a script which starts the pppd daemon on the laptop
The gateway is now waiting for incoming PPP connections
Now we can run a batch file on the IBM 5155, and start the PPP client at 19200 bauds.
The point to point connection is established. Both computers have an IP address on the Serial line
We can now start the web brower : Bobcat, a DOS port of the well known Lynx
There are a few others web browser available for DOS, like Arachnee
But Bobcat is the fastest. Like Lynx, it works in text mode
Most of TCP/IP DOS Software I use on the IBM 5155 was built with the Waterloo TCP/IP Stack
Bobcat is now loading the local home page
Yes, it's slow
Don't forget this computer is running at 4,77 MHz with 640 kb of RAM
Here we are
Now let's connect to
The 5155 is getting the google web page over DSL and serial lines
Transfert is very slow, not only because of limited bandwidth (19200 bps)
But mainly because of limited processing power of the i8088
Keep in mind that at the time of the IBM 5155 release, the World Wide Web and HTML did'nt exist yet
They have been invented 7 years later by Tim Berners-Lee in 1991 at the CERN
Wonderfull : Our 1984 computer is displaying the Google web page !
Let's use the search engine with the word : 'retrocomputing'
Time to make some coffee ;-)
The amount of free memory is limited ...
... so the hard-disk drive is very busy
Voila! Here is the result of our query!
Before leaving, let's make a ping of
0.11 s , not bad for a 25 years old computer ;-)