TCP/IP and Web Browsing on the HP 200LX

Once you’ve configured networking on the HP 200LX, you may be wondering what to do next. Many of the connected applications we use today require a TCP/IP stack. While operating systems such as Windows 95 and above include such networking essentials, the same is not true of MS-DOS. This means that extra work is required to cruise the information superhighway from your palmtop. One solution is the mTCP library and TCP/IP application suite. While it is not a TSR that adds TCP/IP support for use by whichever applications you care to use, it includes a number of utilities that may satisfy all of your networking needs. These include a DHCP client for automatically configuring your connection, PING for confirming connectivity, a Telnet client, an FTP client and server, and even an HTTP server.

To get started with mTCP, download the latest binaries and unzip them on your modern computer. Once extracted, the files total over 1MB, and even for a 2MB 200LX, that’s a big chunk of the available onboard storage, which is the only place you can put mTCP, given that your PCMCIA slot will be occupied by your Ethernet card. When transferring files to your palmtop, you may wish to exclude FTPSRV.EXE and HTTPSERV.EXE, which are each over 100K - since the battery-powered 200LX is probably not the best device to use as a server. You can save more space if you find that there are other EXEs in the collection that you end up not using often - the library is built into each app, so you can run as many or as few as you like, with no concern for dependencies.

One thing that you will want to ensure you have regardless of the tool you use is a configuration file. Copy SAMPLE.CFG from the included SAMPLES directory to the name of your choice (for example, 200.CFG) and at minimum, update the packetint setting. For the Socket Low Power Ethernet CF Card used in our previous post, the interrupt is 0x66. If you are using DHCP, then most of the other settings can be left as-is for now. If you named your config file 200.CFG and extracted mTCP to a folder of the same name, you’ll want to add the following to your AUTOEXEC.BAT:


After doing so, reboot your device (with your Ethernet card installed, configured, and connected) and change directory to C:\MTCP. The first tool you will want to run is DHCP.EXE. This will automatically update your CFG file with your assigned local IP address, DNS, and gateway settings. If you are not using DHCP, or want a static IP, you can update these settings by hand. After completing this step, try PING to ensure you’re connected able to talk to the internet. Feel free to play with whichever tools you like at this point, but some highlights we enjoyed with this setup include:

  • downloading files directly from the S.U.P.E.R Site with HTGET.EXE
  • downloading, modifying, and uploading a web page with FTP.EXE
  • connecting to TELEHACK using TELNET.EXE
Bonus: Browsing the Web

The tools included with mTCP are extremely useful, but there’s one common internet application missing that most people use daily: a web browser! Thankfully, another project built using the mTCP library can fill this need: the MicroWeb web browser for 8088 class machines. Download the latest MICROWEB.EXE from the releases page on the project repo, copy it to the same C:\MTCP folder as the other tools, and run it with the /C option to force 640x200 CGA mode, then start surfing the web! You will probably want to invert the 200LX’s screen using ON+/ (or the software’s own F2 command; for some reason the /I command line option does not seem to work with CGA), and you will discover fairly quickly that many modern web sites force HTTPS, which the 200LX cannot handle, since it lacks the processing power to decrypt data in real time. However, proxy services such as FrogFind can be used to strip modern sites of their JavaScript, CSS, and encryption, making them far easier to view on older machines, and MicroWeb will redirect HTTPS URLs to the service automatically. As the name implies, FrogFind also includes a search engine, since most users are accustomed to tossing vague terms into an omnibox rather than painstakingly entering actual URLs. Since there is no mouse available on most palmtops, you’ll want to familiarize yourself with MicroWeb’s keyboard shortcuts. While MicroWeb does not support images at this time, let alone JavaScript and CSS, and is limited in what it can load by available RAM, it is still an incredibly useful tool for consuming online information.