TEXAS CC-40 REVIEW

THE CC-40 is a battery-powered portable computer from Texas Instruments. At £170, it is in the same price range as the Dragon and the 48K Spectrum and Orics — but that is its only similarity. The Compact Computer will never know the satisfaction of crushing a human at space invaders; it is a machine with a serious purpose.

Up until now Texas has taken care of the home market to its own satisfaction with the TI-99/A. The Compact Computer 40 is an attempt to get into the booming portable market, currently dominated by names like Epson, NewBrain, Casio and Sharp.

The CC-40 weighs a little more than one pound and measures 9.25in. wide by 5.75in. high by 1in. thick — about the size of a big paperback. It can run for 200 hours on four AA size alkaline batteries and it has a built-in 31-character single-line liquid crystal display and good-quality calculator-style keys in a QWERTY layout.

Cartridge slot

Inside, the CC-40 is built around a Texas own-brand eight-bit CMOS chip, the 70C20. It comes with 34K of ROM containing a comprehensive Basic, and 6K of RAM extendable to 18K internally. A cover at the top edge of the machine pulls off to reveal a memory cartridge slot, and a further 16K of RAM can be fitted here, giving an absolute maximum of 34K RAM. Program cartridges also fit into this slot.

Texas expects great things for the new peripherals designed for the CC-40. These include a battery-powered four-colour printer/plotter of the Sharp type, a fast "Wafertape" continuous loop cassette drive like Sinclair's Microdrive, and an RS-232 interface unit for connecting up to big printers and, potentially, other computers.

A Modem and a black and white TV interface are also scheduled for release later in the year. The CC-40 system is clearly aimed at people using computers for their work; but this could include students of scientific or engineering subjects as well as professional users.

The whole machine is well made. For instance, along the bottom of the machine runs a recessed stand, which can be pulled down to tilt the keyboard to a nice angle for typing. There will be no need for entrepreneurs to offer adaptor feet at £4 a pair. (A reference to the "HI-STAK" feet sold for the Sinclair Spectrum which were just two self-adhesive plastic wedges to be stuck under the back, to tip the keyboard forwards.)

The casing itself is made from a silvery-grey plastic, except for the numeric keypad, a few of the other keys and the area around the screen, which are highlighted in a darker grey.

At the back of the machine is a slot for the optional AC adaptor which costs £14.95, and the Hex-bus connector, into which all the peripherals will fit.

There were no problems with the keyboard. The calculator-like keys feel comfortable and give tactile feedback. The layout is fairly close to the standard QWERTY pattern, but the Enter key, the Texas equivalent of Return, is rather annoyingly positioned where you might expect the right-hand shift key to be.

Given the size of the CC-40 the keys are obviously smaller than on a standard typewriter, but they are easy to use and larger than on the Sharp PC-1500 for instance, a machine with virtually the same price and an obvious competitor.

The CC-40 comes with a plastic keyboard overlay, which among other things has the principle Basic keywords on it. Basic keywords can either be typed in full in the normal way, or by using the function key then hitting the appropriate single key given on the overlay, the machine can be made to produce them Sinclair-style on the display. This is a useful time-saving feature, although the overlay itself might soon be lost.

Program scrolling

The display is a single line of 31 characters, but this can be used as a window on to an 80-character line. The arrow keys above the keypad can be used to scroll around horizontally within the line, or to step vertically within through a program listing. With a little practice the small display does not seem such a limitation, although for developing long programs the printer at £149.95, would be essential.

On the side of the machine to the left of the display is a knurled wheel. Turning this adjusts the display angle electronically, so you can aim it at yourself to get the best contrast.

The characters are formed on a five-by-eight matrix, and like all LCD displays are much less tiring to watch than a TV screen. The lack of colour confirms that this is a working machine, rather than an entertainment device.

On both sides of the actual text line in the display one finds indicators showing battery-low warnings, upper-case lock on, Function, and which units the trigonometric functions are currently returning value in.

The machine can be used as a calculator. It works exactly the same as Basic in immediate mode, but on the CC-40 it is not necessary to type Print before a calculation. You just key in 8*63 and then hit Enter, and it gives you the answer.

The up-arrow key, used with Control held down, functions as a playback key. Hitting it brings back the last line entered on to the display, where it can be edited, and the calculations redone. This saves time if you have entered a long complex calculation and want to try it out with a few different values.

For anything more complex there is Basic, and the CC-40 has a very full Basic. Again, it is practically oriented. There are no sound commands to support the small internal beeper, only the feeble Beep, but this is sufficient for attracting attention.

The numeric precision is good — 10 displayed digits — but the machine is not very fast. Battery-powered CMOS machines are inherently slow.

If your foreign languages need brushing up try,    Call Setting 1
This puts out all the error messages in German — Variable nicht definiert — and that sort of thing. Other languages are available on ROM cartridges.

The Basic has all the usual commands of Microsoft-style Basic. It includes If...Then...Else, On...Goto/Gosub/Error, Print Using to format output conveniently, and various file control commands for use with the Wafertape, like Open, Print#, Input#, and Verify. Three-dimensional arrays are allowed, and long variable names.

Strings can be up to 255 characters long. String handling works differently to most home micros. Instead of Left$, Mid$, Right$ the CC-40 has a Seg$ command for extracting substrings, and a Pos command to find them.

Another addition is the way subroutines are handled. Gosub is there and can be used in the normal way, but there are several more powerful commands allowing you to set up sub-programs. These are called with a Call statement and an optional set of parameters.

The 35K ROM contains a number of useful sub-programs. Call Debug gets you into a machine-code monitor, with all the usual Examine, Move, Copy and start Executing commands, plus the ability to set Breakpoints.

The CC-40 manual which describes all this is extemely good. It is a 300-page professional manual, not just a home micro manual.

Ready-written software will be available on cartridges and Wafertapes. Statistics, Finance, Maths and Electronics cartridges should be available immediately, with Perspective drawing, business graphics and a few others hot on their heels according to Texas. These all cost £59.95. Two games cartridges cost nearly £40, and the Assembler nearly £125, so software is not cheap.

The Wafertapes will be cheaper, just under £20. Again the announced titles look fairly professional — things like Elementary Dynamics, Pipe Design, Profitability Analysis. Texas hopes to find third-party software suppliers to contribute additional titles.    ¨