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Allen Gelder Software San Francisco, CA $19.95

by Mendel Cooper

Shortly after introducing the TRS-80, Radio Shack brought out a stripped-down machine-code monitor and debugger, T-Bug. At the time, T-Bug was the only game in town and you bought it. Now there are much better monitors on the market, and you may well regret your $15 Investment.

Into a Heavyweight

SuperStep transforms the lowly T-Bug into a heavyweight. It offers single-stepping, a two-speed trace mode, and a versatile disassembler that can run in conjunction with the single-step or trace modes. A processor model displays all registers and flags, both for the current instruction and for the previous one. An intelligent RAM window shows the RAM locations and contents affected by memory accesses.

SuperStep has commands that backspace in memory, clear the screen, and display memory contents in rows of 16—In hex or in ASCII. It gives direct access to the registers (each one labeled) and to the flags (each one individually set). There is also a relative-jump pointer that shows where you are jumping to— and can even take you there, and back. There is a high-speed save/load command included in the package. Regrettably, this one will not work on my machine because it has the XRX cassette load modification.

SuperStep's string editor allows Inserting or deleting bytes in a sequence of code. The bytes on either side of the change move aside or close up, as necessary. Useful for editing ASCII strings or tables, this feature also allows creating or deleting space within a program. A patch can now have enough space to reside entirely within the program it modifies; it no longer need jump elsewhere to do its work (you would still need to fix up the Jumps and Calls, of course).

An Invaluable Aid

I rate SuperStep as the best single program I have in my modest collection. If the program is useful as a debugger, it is in-v^Kigble as an aid to learning Assembly language jp#bgramming, and the Z-80 Instruction set in particular. As the program's author states, SuperStep cuts down on the "imaginative overhead" of the programmer. William Barden, in his book TRS-80 Assembly Language Pro gramming, advises his readers to "play computer" as a means to understanding

for you, and with more precision and

Fractional Sound The Innovative Penguin Harvey, LA $14.96 cassette $18.95 disk by Mary S. Gasiorowski

Fractional Sound is a fractional drill program for the Model I Level II, or Model III 16K (or Disk Basic, 32K), with sound (by connecting the auxiliary plug to an amplifier). The program allows you to set parameters for: the type of operation (add, subtract, multiply, divide, or mixed types), maximum size of numerator and denominator, whether mixed fractions are allowed, and the number of students involved; it will also allow you to put in your own problems, if you want.

Bad Point

The format for putting in the answer is extremely awkward. You have to Identify which of the eight positions each number of your answer goes into (two for the whole number, three for the numerator and three for the denominator). If you (and your kids) can get used to that, then the rest is easy.

greater clarity than the paper-and-pencil method.

I do have a couple of minor bones to pick with the program's author. The documentation needs to be revised and reorganized. It could be greatly expanded, with many more examples. But this is hardly a fatal shortcoming since you learn to use this program by using it and experimenting.

The only real reservation I have about the program is that it needs T-Bug to run. SuperStep is a steal at its price, but you must also pay $15 for T-Bug. Perhaps Gelder will rewrite the program as a standalone monitor.®

Good Points

The program generates easy-to-read large (5/8 inch for numbers in fractions, two inches for whole numbers) numbers on the screen, and a random tone ticking sound while it's waiting, as well as a bugle charge when your answer is correct, and other miscellaneous sounds.

If you get a problem wrong (it informs you), the program goes into its waiting mode. It will explain step-by-step how to do the problem as long as you press a key each time to continue.

One nice feature is that a correct but unsimplified answer is not counted as wrong. Many programs will accept only the simplified answer, which can be frustrating for a child who has done the work of combining the fractions, but because he neglected to simplify, gets no credit for his work. In Fractional Sound, if you combine the fractions correctly but neglect to simplify, you are told to simplify your answer and continue.

On occasion during the drill, a graphics character (Marley Mole) appears to encourage you. He wants you to come out and play a game with him.

At the end of the drill is a little game—fence in the moving dot (Marley Mole) without getting trapped first. It's a nice little game, appropriate for the intended age level of Fractional Sound.■

"In Fractional Sound, if you combine the fractions correctly but neglect to simplify, you are told to simplify your answer and continue."

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