Epson HX-20 Floppy Disk and Screen Simulator

[norbert_kehrer]

Hi,

the Epson HX-20 handheld computer offered an interesting way to connect it with peripheral devices. The serial port at the back of the computer can talk to external hardware using an Epson-specific protocol for data exchange. As this protocol is quite well documented, I wrote a little program called "flashx20" (for FLoppy And Screen for the HX-20), which allows to connect a normal Windows PC or notebook computer to the HX-20. The PC interprets the Epson serial protocol and simulates an external display controller and four external floppy disk drives.

With that, you get a big screen (the PC monitor) and disk space for Epson programs and data on the PC's hard disk. To transfer, for example, a BASIC program from the PC to the HX-20 just copy an ASCII file with the program to the flashx20 directory on the PC. Flashx20 also has graphics support. The commands to draw dots and lines available in Epson BASIC can be used to create high-resolution pictures in up to 8 colors on the screen of the Windows PC.

The software is downloadable as a zip file containing the "flashx20" program, some BASIC examples and graphics demos, and the pdf user manual.

You find it on my website at http://members.aon.at/nkehrer/

Norbert