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From: PORTABLE 100, March 1989, pgs 8–13.

Get WordStar cursor control for TEXT.

By Stan Wong

Repub and bugfixes, extensions by John R. Hogerhuis

I'm a WordStar addict. There is nothing flashy about the program. It's not even sexy. But I love WordStar and its arcane cursor movement and control commands. It was, and still is, one of the few word processing programs supported across many different machines and operating systems. I use it on a DEC Rainbow and a 386 PC at work. I use it on my IBM PC/XT. And I bought an NEC 8500 CP/M laptop because it had WordStar built in.

My fingers get cramps every time I use my trusty Model 100, and trying to remember the different cursor movement and editing commands drives me batty.

Well, no more!

A Diamond in the Rough

The Model 100 TEXT program already implements the famous WordStar cursor control-character "diamond" – ^S, ^E, ^D, ^X, where the caret (^) signifies holding down the CTRL key, as WordStar users know – but it doesn't go far enough.

So I've polished up the diamond a bit. I've written a small machine language program called TextStar (or Text* to its friends), which implements most of the WordStar cursor movement commands as well as some text deletion and other miscellaneous commands.

TextStar is not a complete program by itself. Instead, it enhances the operation of TEXT. Although TextStar's cursor control looks and feels like WordStar, it still retains a TEXT-like flavor. See the sidebar "Inside TextStar" for technical information on how it performs its magic.

TextStar extends the operation of TEXT by redefining the meaning of the control keys, where possible, to match those of WordStar (See Table 1). Even multiple-keystroke commands such as ^QD, are supported. Control keys that have not been redefined still retain their TEXT meanings. For instance, ^B still moves the cursor to the bottom of the screen. ^T will not, however move you to the top of the screen but will delete a word instead.

A simple change to TextStar could have made it ignore the TEXT control keys, but I felt it would be better to leave them in. The program owes its small size (381 bytes) to its method; it traps keyboard input and translates only WordStar control codes into their TEXT equivalents, passing all other keystrokes directly to TEXT for normal processing.

Vive La Difference

However, TextStar does not perform exactly like WordStar. Because it enhances the TEXT program, it is bound by certain TEXT conventions.

For instance, when moving up and down a line, WordStar moves the cursor to the end of a line if the destination line is shorter. But TextStar, like TEXT, leaves the cursor in the same column regardless of the destination line's length.

As a bonus, the text deletion commands ^T and ^Y store the deleted text in the paste buffer. So if you make a mistake you can recover the text by pressing the PASTE key. This gives you a simple UNDO facility.

A Star Is Born

Listing 1 is a relocating BASIC loader. It creates a machine language program, TXTSTR.CO, to run anywhere you specify in high memory, or it will default to loading just under the current HIMEM. It can thus coexist with your other .CO programs. (Thanks to Phil Wheeler for his BASBLD.PW3 program, which I used to create the loader.)

Listing 2 is the assembly language source code for TextStar. I used the ADSM assembler by James Yi, which you can find on the CompuServe Model 100 Forum. Minor syntax changes to the source code will also make it compatible with the ROM2 assembler from Traveling Software, which I used to do the initial program development.

You have no need to use the assembly language listing, however, other than to understand what TextStar is doing and how it does it.

A Rising Star

To run TextStar, place the widebar cursor over TXTSTR.CO on the main menu and press ENTER. You should then see TEXT's familiar File to edit? prompt. Specify the .DO file to edit, and you're on your way.

If the program doesn't start, go into BASIC and type CLEAR 0, nnnm (where nnnm is the load point) and then try again. If you don't know the load point, type LOADM "TXTSTR" and use the Top address returned by the LOADM command as the load point (nnnm) for the CLEAR statement above.

Where To Get TextStar

TextStar is also available on the P100-To-Go disk and on the Portable BBS (603-924-9770) as TXTSTR.100. If you need the program and listings on a cassette tape, send $6 to me at P.O. Box 28181, Santa Ana, CA 92799. You can also contact me via CompuServe user ID 70346,1267. I support the program on the M100SIG of CompuServe.

Those cramps in my fingers are finally starting to disappear. Happy typing!