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TAPE SPEED CHECKER / SPEED CHECKER: TAPE TROUBLES (Amstrad Action) | TAPE SPEED CHECKER / SPEED CHECKER: TAPE TROUBLES (The Amstrad User) |
Some guidance on how to deal with tape errors including a Tape Speed check program. Messages, messages - the erroneous type Cassette users see those familiar read or write error messages rather too frequently. Message pops up, system crashes. All very infuriating. Here is an analysis of these errors - when they occur and why. Read Error a: The data bit read was too long. This occurs if the cassette is halted during loading or cataloguing. It may even happen if there is a lot of wow. ('Wow' sounds like what it means: the tape motor running at an uneven speed). Read Error b: There has been a CRC (cyclic redundancy check) fail. This is the most common of the errors and can occur if there is dust or a defect on the tape surface. Read Error d: I tried desperately to attain this error message, but failed to do so, It indicates that the block read was too long. The only way to get this error, it seems, is to program it deliberately. Write Error a: The write frequency is set too high. This again can only be programmed intentionally. So you shouldn't ever encounter this and the previous error message. We have - but don't want Read errors can be caused by dirty tape heads or pinch rollers - this could lie with any tape deck. In Amstrad 664 and 6128 machines, the problem could be with improper setting of volume and tone controls. Owners of the 464 don't have this problem as these levels are preset. Your recording heads could do with a good clean fairly often -especially if you frequently use low-grade cassettes. The best way is with cotton buds dipped in methylated spirits (or Isopropyl Alcohol). Definitely do not use abrasive detergents or sharp objects. Ensure that the head is dry when you finish. As well as the head, the pinch roller (usually rubber, to one side of the mechanism) should be given the treatment. Using a cleaning tape', which you can buy from a hi-fi shop, will give the best results. Dirty pinch rollers can be the cause of many a problem: they can make the tape speed vary or, even worse, they can eat or crease your tape. One final step to improve the performance of your cassette deck is to align the tape head - the azimuth angle. Azimuth, from Latin, means 'degrees of arc above the horizontal'. In the case of cassette players, it means the angle of the head relative to the horizon - the magnetic tape inside the cassette shell. There are various commercial azimuth aligners on the market and in the first instance you could enquire with your local hi-fi dealer. On the outside trying to get in? The 664 and 6128 machines need an external cassette recorder if tape programs are to be loaded into memory. Naturally, a new set of problems is likely to come into play. Positioning of the cassette deck and leads can be crucial for satisfactory loading or saving. The recorder should not be too close to any magnetic field - such as the monitor. Likewise, the leads shouldn't run parallel to mains leads, or close to magnetic fields. The reason is that tiny impulses in the cassette leads can easily be distorted. (And of course tapes or disks should never be placed on top of the monitor.) Whenever possible, use a tape deck that runs from mains electricity. Battery-operated decks are prone to fluctuating power signals, which causes a degree of wow. Everyone's favourite now:tone and volume settings. (Memories from my Spectrum programming days). Being the hardest and the most annoying to set correctly, they are the most common cause of data loss. The volume should be set fairly high. However, if it's too loud, distortion results - poor old Arnold will get an earache. The tone should be set between three-quarters and full, giving a high (trebley) sound. If you go carefully through all these procedures and you still have read/write problems, there is either something wrong with your tapedeck or the software you are trying to load is faulty (ie. the tape has been corrupted). One point I failed to mention concerning external cassette decks: you may not have remote-control or your deck. This causes problems when loading certain commercial software that insists on stopping the cassette motor while it draws a title screen or something. There is no simple way of overcoming this problem. The only tiling 1 can suggest is that every time you hear a relay click in your CPC, pause the tape till another dick. There is certain, very old, software that insists on having all the memory it can grab. Machines with a disc drive will reserve about 500 bytes of memory - if not more. The result is that these software packages will not run on your Amstrad. Here isa short program that will reclaim all memory, giving a completely free machine. 10 FOR t=&A000 TO &A017Tape Speed Check program |
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