INMC 80 News


May–September 1981, Issue 4

Page 8 of 71

Anyway enough of that, I have a couple of problems which despite much book and magazine searching haven’t been resolved.

The first is the INP function, would it be possible to write a section on how this works and when we use it. I’ve found it in a Computing Today program and cannot fathom out how it works at all.

The second problem is that of a timer to indicate how long a program has run.

To give an example – lets say that we wished to time how long a pupil took to do ‘say 10 sums’. How could we do this? The PET has a time function but such a function is not available on our Basic. Is there a machine code sub-routine to do this – such a routine would be extremely useful to me.

Once again thanks for a great machine – hope it keeps going for many years.

WD Cooper, ___ ______ ____, Newcastle upon Tyne. ____ ___.

Funny Tapes?

As Nascom Dealers we frequently encounter customers with a low opinion of cassette tape as a storage medium despite us knowing that the hardware is totally satisfactory. Such customers invariable ignore what we now believe to be the true cause – sub-standard cassette tapes! In common with other Dealers we sell blank C10 or C12 cassette tapes believing them to be “screened against drop-outs” and therefore suitable for the recording of digital data. After trying the wares of many suppliers of “screened” tapes (this includes a number of well-known “branded” products) we have now come to the conclusion that if, indeed, they are tested for drop-outs, then the test criteria are totally inadequate. We name no names because it seems that all suppliers offer the same (abysmally low) standard.

Among problems that we have so far encountered are:–
Errors because the tape gets creased by most normal cassette recorders.
Errors because over-recording does not erase the old data.
Errors because a tape is read fairly frequently and wears out very quickly.
No (yes NO!) oxide layer on the tape. (It took a long time trying to decide if this was a “Read” error or a “Write” error!)

When asked, suppliers invariably say that since no other customers have problems, “it must be you” (does this mean all other customers are using low baud rates such as that used by TRS80 etc. and can therefore be supplied with low quality tapes without repercussion?)

In view of this widespread problem, have any of your readers found a source of supply that is always reliable?

Richard S. Marshall, Chief Engineer, Business & Leisure Micro Computers.


1 Nascom 3A PSU built – 25.00 ono
1 5″ wide module for Vero frame – 5.00 ono.
1 16K RAM A board built – 90.00 ono
’Phone Kevin on Aberdeen (____) _____.

Nascom 2. Nas-sys, Nas-dis, Debug, Zeap, Graphics, 32K Basic, Basic Toolkit, Word processor (Wordease?), Music Box, 12/2400 Baud, all in Eprom. V.D.U. and cassette, approx. 40 tapes, all documentation, Epson TX-80B printer. Around 1,000.00 ’phone ____ ______ or ____ ______.

Licon Switches with blank caps to update Nascom 1 keyboard 1.65 each or 15.65 for 10 incl VAT + 35p per order P & P (see INMC80 Issue 2 and Liverpool Software Gazette for connections). Chiatronix Ltd., 22 St. Michaels Avenue, Houghton Regis, Dunstable, Beds. ’Phone ____ _____

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