Reviewer: Kathleen Peel

Magazine: Your Computer

Date: October 1983

### Tandy's latest package - the MC-10 microcomputer and the TP-10 thermal printer - is aimed at the computing novice. Is it suitable for the beginner? How does it compare with the well-established Spectrum and Oric? Kathleen Peel investigates.

Tandy has recently brought out a number of new machines aimed at increasing sales and revitalising the product range. The Model 100 will do just that in the portable market, but whether the MC-10 will have the same success remains to be seen.

The MC-10 is aimed at the computing novice who wishes to learn about computing on a simple no frills Basic machine. It will be launched with a compatible new thermal printer, the TP-10, priced mid-way between the low cost/low quality ZX printer and the highly successful badge-engineered Sharp four-colour printer/plotter.

The computer is based on the 6803 processor - a 6801 without the on-chip 2K ROM - and the MC6847 video display generator. 4K of user RAM is provided which may be extended to 20K by using a RAMpack. The computer is capable of displaying nine colours and of producing sound through the television speaker.

As with all Tandy products, there is little one can criticise in the quality of the construction. The robust case - the unit weighs nearly 2lbs - contains a printed circuit-board which is well laid out without any changes or modificitions.

The keyboard is ¾ full size and looks small; hard plastic keys provide a feel as good as any other keyboard of this type and at least there is a spacebar. There is, however, no audio feedback or auto-repeat on the keys.

Words may be typed in full or control-keyed in if it is a keyword and if it is above one of the keys. It is good that both are available but as not all the common keywords are represented you do tend to spend rather a long time looking for those not there. I wonder who decided to put the Break Key just above Enter - I thought this type of mistake had been eliminated, but it is tending to creep back with, perhaps, a new generation of designers not having learnt from their predecessors' mistakes.

At the rear of the computer there are connectors for the AC adapter, the TV connecting cable, a 5-pin DIN socket for the RS232 interface, an edge connector for the memory expansion protected by a cover plate and also a Reset button, used to provide a warm start.

The first problem with the operating system is the editor - there isn't one! You cannot edit an existing line, all that is available is a simple backspace delete to correct a line as it is entered and a line delete to remove it altogether when you have lost patience. Error messages are given by two letter abbreviations; far better than error numbers but still not as good as the full error message.

For a machine aimed at the novice, the meanings given for the error messages might just as well be in Latin for all the good they are to the beginner; for instance out of string space or file mode error. They need to be explained with many examples to be of serious use. Switching on will produce the message:

    MICROCOLOR BASIC 1.0
    COPYRIGHT 1982 MICROSOFT
    OK

written in black letters on a green background with a black border. Print Mem obtains the amount of free space left for your programs, 3142 bytes initially.

The cassette interface operates at 1500 Baud and appears reliable. Speed variations of -12 percent to +20 percent were tolerated and the three modes of cassette Saving were all satisfactory, manual, manual with peak clipping and automatic, all with considerable tolerance on the level of playback.

On loading a tape, the computer clears the screen and places an S - searching - in the top left hander corner, an F - file name - shows the file has been found, followed by OK on completion of loading.

Program 1 can be used to list all the ROM keywords, and note that they are not all listed in the manual. The Basic is Microsoft Basic, all the keywords have their standard meanings and there are even simple structures On...Gosub and On...Goto. Table 1 gives speed comparisons with the Spectrum and Oric.

Displays may be created using the quartered graphic block characters which can be any two of the available nine colour in each - 32 by 16 - character position. This produces an effective pixel resolution of 64 by 32 and a colour resolution of 32 by 32. Alternatively the pixels may be set - switched on - and reset - switched off.

There are no draw or circle commands. Whether this level of resolution is adequate in today's market is debatable.

The sound is produced through the telvision's loudspeaker and so may be as quiet or loud as is required. It is only a single channel but, with the added external volume control, is a considerable improvement over the Spectrum beep. The sound may be varied in frequency and duration.

With the MC-10 comes the Operation and Language Reference Manual and a notice for non-American users. Accepting that the MC-10 is for the novice, it is difficult to know what to say. The beginning of the manual is so obviously intended for the American user, it is going to confuse the beginner before he has even got the computer wired up.

The correction notice does not cover all the necessary references to the American system. The one saving grace is that this machine will only be supplied through Tandy stores and from them you will at least get expert advice on how to set the computer up.

The remainder of the manual on learning and using Microcolour Basic is quite good. There is even a summary sheet which contains all the Basic statements with syntax, error messages, functions, etc. a nice idea.

I would advise early purchasers to obtain Tandy's Qetting Started with Colour Basic. Many of the Basic programs will work on the MC-10 as they stand and even though a number of the chapters are specifically for the Colour Computer, it is perhaps a good starting book.

To enable machine-code programs to Run CloadM, Exec and USR are implemented in the Basic. The machine also seems to understand the joystick commands, but quite where they will be fitted I am not sure.

There are obvious differences between the MC-10 and the Colour Computer besides price; the display file has been moved and generally the memory map has been changed.

It remains to be seen whether the user can access the page select register, video display generator and display control register to obtain the high-resolution of the Colour Computer.

Compatible with the MC-10 and the Colour Computer, the TP-l0 RS232 thermal printer manufactured by Canon for Tandy is destined to become very popular.

The printer is 8 by 6 by 3 and weighs 3½lbs. It prints 30 characters per second, 32 characters per line on 3½ inch wide thermal paper with a line separation of 0.167 inch. The grey case matches that of the MC-10 and the TP-l0 is also very well made. The print head is tracked across the paper by a stepper motor which operates extremely quietly, the only noise is on the line feed mechanism. The printed-circuit board is well laid out with the sensitive circuits well screened.

There are two operational~switches, a rocker on/off at the side and a membrane type touch switch for the paper feed. An led indicates power on/off and will flash if the print head jams.

The printer operates at 600 Baud with one start bit, eight data bits and two stop bits - no parity.

Files may be LList to the printer and you can also LPrint a line, but their is no copy facility on the MC-10 to produce a screen dump which is a pity. Having created a masterpiece on the screen, to make a hard copy requires every line with a print statement to be retyped in full - there is no editor.

Do not try to Reset or to Save the cassette with the TP-10 connected to your computer as the printer starts to produce garbage if you do. I also found occasionally that the print buffer was not cleared from previous calls. As this machine is alleged to be compatible with the MC-10, this particular problem is hard to understand, a bit disturbing but no real problem.

Paper loading was simple and straightforward, cut a reasonable edge, feed into slot and press the paper advance button - very good.

The instruction set is given in Table 2. There is provision for double width printing, underscoring, overwriting and repeating characters. The alphanumeric characters are made up of a 5 by 7 dot matrix, the graphics characters are produced in a 7 by 12 dot matrix which interestingly means that the graphic quarter blocks are unequal in size, the left hand quarter blocks are 3 by 6 and the right hand blocks 4 by 6. Figure 1 gives the printer dump of the character set.

The print quality is very good. Figure 1 which shows the full character set also demonstrates the only minor faults of the printer - no pound sign and no lower case descenders for g, p and q. The print is exceptionally clear, one can even pick out the individual dots in the graphics characters. An excellent well laid out manual should get anybody started.

Prices: The MC-10 is £99.95; TP-l0 is £79.95; RAMpack is £39.95, and paper rolls are £2.79 pack of two.

## CONCLUSIONS

- Vithout high-resolution graphics, I think the MC-10 is over-priced. It is effectively a ZX81 with colour, sound and a better keyboard which, compared to the 16K Spectrum with its established software base, makes the MC-10 a non-runner. A year ago when there was significantly lesss choice it might have developed a following, but. now there are too many better machines available.
- The TP-10 is a different story. Tandy seems to have the ability to pick quality accessories to go with its products and this is no exception. The print quality is good and for £80 represents extremely good value for an RS232 printer.
- The running costs will probably be lower than the ZX printer so I think there will be a very large number of Spectrum owners who, when they acquire their Microdrive interface, will find this an extremely acceptable printer. The graphics characters are not the same for the two machines so the Spectrum will require a translator. I can see no reason why the Spectrum copy facility should not work.

Program 1.

    5 LPRINT
    10 FORA=49221T049479
    20 IFPEEK(A)>120THEN6O
    30 LPRINTCHR$(PEEK(A));
    40 NEXTA
    50 STOP
    60 LPRINTCHR$(PEEK(A)-128),
    70 GOTO40

ROM keyword dump.

    FOR	GOTO
    GOSUB	REM
    IF	DATA
    PRINT	ON
    INPUT	END
    NEXT	DIM
    READ	LET
    RUN	RESTORE
    RETURN	STOP
    POKE	CONT
    LIST	CLEAR
    NEW	CLOAD
    CSAVE	LLIST
    LPRINT	SET
    RESET	CLS
    SOUND	EXEC
    SKIPF	TAB(.
    TO	THEN
    NOT	STEP
    OFF	+
    -       *
    /       ^
    AND	OR
    >    =
    <	SGN
    INT	ABS
    USR	RND
    SQR	LOG
    EXP	SIN
    COS	TAN
    PEEK	LEN
    STR$	VAL
    ASC	CHR$
    LEFT$	RIGHT$
    MID$	POINT
    VARPTR	INKEY$
    MEM

Table 1. Speed comparison

| MC-10 | SPECTRUM | ORIC
--- | --- | --- | ---
TIME TO LOAD ARRAY (Secs) | 8 | 13 | 15
TIME TO SORT ARRAY (Secs) | 184 | 261 | 300
SPACE OCCUPIED BY PROGRAM | 227 | 339 | ns
SPACE OCCUPIED BY VARIABLES | 5033 | 5037 | 5036

Table 2.

CODE | FUNCTION
--- | ---
CHR$(10) | linefeed
CHR$(13) | Return with linefeed
CHR$(26) | Return without linefeed
CHR$(27) CHR$(14) | Elongated mode on
CHR$(27) CHR$(15) | Elongated mode off
CHR$(28) CHR$(n) CHR$(m) | Repeat n times (0-255) ASCII code m
or CHR$(28) CHR$(5) "T" | Prints five T's